a product - selling - data processing apparatus according to the first embodiment of the present invention will be described in more detail with reference to fig1 to 7 . a pos system ( a product - selling - data processing apparatus ) includes a plurality of pos terminals 11 , a file processor ( fp ) 13 and a communication - line 15 , and each pos terminal connects the file processor 13 through the communication - line 15 . there are two types of pos terminals , one is a master terminal 11m ( m - tm ) and the others are satellite terminals 11s ( s - tm ). usually the file processor 13 is connected with one master terminal 11m and a plurality of satellite terminals 11s . the satellite terminals 11s have a function , such as transmission of the article selling data which is inputted to the file processor 13 and issuing a paper receipt on which the article selling data is printed . the master terminal 11m has a first function which is the same as that of the satellite terminal , and a second function which allows an article code to be added to or eliminated from the article file 7 in the file processor 13 . file processor 13 is provided with an article file 17 ( memory means ). the article file 17 includes an article code column 17a including a plurality of rows for storing different article codes respectively , an article name data column 17b for storing the article name data corresponding to each article code , a unit price data column 17c for storing the unit price data of an article or the unit price data of a bundle - of - selling article corresponding to each article code , total sold article number data column 17d for storing the number of sales of each article corresponding to each article code , and total sold amount data column 17e for storing the total sold amount data for each article corresponding to each article code . the article code column 17a , the article name data column 17b , and the unit price data column 17c correspond to an article information memory section , and the total sold article number data column 17d and the total sold amount data column 17e correspond to an article selling data memory section . this pos terminal 11 is generally installed on the floor of a supermarket for example . as shown in fig3 the pos terminal comprises a cpu 19 , a rom 21 , a ram 23 , a communication interface 25 , a keyboard controller 27 , a display controller 31 , a print controller 35 , and an i / o port 39 . these circuit elements are connected to one another through bus line 47 consisting of address , data , and control buses . the keyboard controller 27 is connected to a keyboard 29 , the display controller 31 is connected to a display section 33 and the print controller 35 is connected to a printing section 37 . a selection signal is inputted to the i / o port 39 in response to a selection through a mode switch 41 . the mode switch 41 is to select one of a plurality of modes which are the registration , checking , clearing and establishment modes , by rotating the key type switch . the cpu 19 performs a transaction of registration , checking , clearing , or establishment in accordance with the selection signal . a reading signal fed from a bar code scanner 43 ( article code inputting means ) is inputted to the i / o port 39 . a drawer 45 temporarily stores some money and is opened by an opening signal output from the i / o port 39 . the rom 21 stores control programs for the cpu 19 . upon prosecution of the control programs stored in the rom 21 , the cpu 19 performs operations in the registration , check , clearing , or establishment mode . the ram 23 stores data inputted to and output from the cpu 19 in these operations . the communication interface 25 is used to control data communication with a file processor 13 installed in an office to manage various job files . for example , an inquiry about prices of items , and a transaction report are performed through the communication interface 25 . the keyboard controller 27 controls the keyboard 29 and supplies the key input data from the keyboard 29 to the cpu 19 . the display controller 31 controls the display section 33 to cause display data from the cpu 19 to be displayed on the display section 33 . the printing controller 35 controls the printing section 37 to cause printing data supplied from the cpu 19 to be printed at the printing section 37 . a plurality of numeric keys 49 , a clearing key 51 , a multiplication key 52 , a subtotal key 53 , a total key 55 , and bundle - of - selling proclamation keys 57 ( indicating data input means ), and so on , are arranged on the top of the keyboard 29 as shown in fig4 . the bundle - of - selling proclamation key 57 includes three different keys , for example a first key 57a ( thereinafter refered as a three bundling key ) is used when the number of articles sold as a bundle - of - selling is three . a second key 57b ( hereinafter refered as a five bundling key ) is used when the number of articles sold as a bundle - of - selling is five . a third key 57c ( hereinafter refered as a seven bundling key ) is used when the number of articles sold as a bundle - of - selling is seven . as shown in fig5 ram 23 includes an article code memory 59 for storing each article code indicating a registered article , a bundled article number data memory 61 for storing a bundle - of - selling number data ( n ) which is indicated by one of the bundle - of - selling proclamation keys 57 . ram 23 also includes a flag data memory 63 for storing &# 34 ; 1 &# 34 ;, as a bundling flag data ( f ) ( a bundle - of - selling indicating data ), when the bundle - of - selling is performed . the cpu 19 performs a transaction , as shown in fig6 when one of the bundle - of - selling proclamation keys 57 on the keyboard 29 is operated under the registration mode which has been selected by the mode switch 41 . thus , &# 34 ; 1 &# 34 ; is established in the flag data memory 63 as the bundling flag data ( f ), and the number of corresponding bundle articles to be sold ( n ) is stored in the bundled article number data memory 61 . the cpu 19 further performs a transaction as shown in fig7 . in step st1 , bar code data , converted from an article code , which is generally attached to an article as a bar code label is read by bar code scanner 43 . the bar code data output from bar code scanner 43 is inversely converted to the article code ( in step st2 ) and the article code is stored in the article code memory 59 ( in step st3 ). in step st4 , the status of the bundling flag data ( f ) in the flag data memory 63 is examined . if &# 34 ; 1 &# 34 ; is stored in the flag data memory 63 as the bundling flag data ( f ), the yes - path is taken . otherwise , the no - path is taken . when the yes - path is taken in step st4 , an article code for the bundle - of - selling is framed based on the article code memorized in the article code memory 59 ( in step st5 ). the article code for the bundle - of - selling is framed such that the bundled article number data ( n ) memorized in the bundled article number memory 61 is added , as a head figure , to the numerical row of the article code memorized in the article code memory 59 . in step st6 , the bundling flag data ( f ) in the flag data memory 63 is cleared to &# 34 ; 0 &# 34 ;. in step st7 , the article information data , including article name data and article unit price data , which corresponds to the article code for the bundle - of - selling framed in step st5 , is inquired to the file processor 13 . ( first calculation means ) the pos terminal 11 receives a response from the file processor 13 . in step st8 , the response is examined . if the article information data is received , the yes - path is taken . otherwise , the no - path is taken . when the yes - path is taken in step st8 , the article selling data ( a selling data ) is obtained in accordance with the article information data . the article selling data includes a sold article number data and a sold amount data . the article selling data is transmitted to the file processor 13 . the article selling data is added to the previously memorized article selling data in the article file 17 ( in step st10 ). if the no - path is taken in step 4 , the above - described step st7 is executed . the article information data in accordance with the article code which is memorized in the article code memory 59 is inquired to the file processor 13 . ( second calculation means ) the subsequent transaction is the same as that of the above - described step st7 . the file processor 13 searches the article file 17 in accordance with the article code which is transmitted from the pos terminal 11 when the file processor 13 receives the article code from the pos terminal 11 . if the same article code as the article code transmitted from pos terminal 11 is memorized in the article file 17 , the article information data in correspondence with the article code transmitted is read out from the article file 17 . the article information data is transmitted to the pos terminal 11 which inquired to the file processor 13 . if the file processor 13 receives data which is the article code and the article selling data ( i . e . a sold article number data and a sold amount data ) from the pos terminal 11 , the article selling data is added to the previously memorized article selling data in the article file 17 . the sold article number data is added to the previously memorized sold article number data in the total sold article number data area 17d in correspondence with the article code received . the sold amount data is added to the previously memorized total sold amount data area 17e in correspondence with the article code received . ( first memory control means and second memory control means ) according to the first embodiment , the article information data and the article selling data are memorized in article file 17 in correspondence with the article code of each article . so , on the bundle - of - selling articles , the article information data and the article selling data are memorized in correspondence with the article code for the bundle - of - selling . the article code for the bundle - of - selling is framed by additionally affixing the bundle article number data at the head figure of the article code which is used by an article selling . the article name data and the unit price data are memorized as the article information data of each the article and name data for the bundle - of - selling article and selling amount data are memorized as the article information data of the bundle - of - selling articles . for example , as shown at fig2 if three chocolates whose article code is [ 000000000001 ] are sold as the bundle - of - selling , the article code for the bundle - of - selling becomes [ 3000000000001 ] if five , the article code for the bundle - of - selling becomes [ 5000000000001 ] and if seven , the article code for the bundle - of - selling becomes [ 7000000000001 ]. the bar code label is affixed to the article [ chocolate ]. the bar code is printed on the bar code label . the bar code is converted from the article code of the chocolate . in case a predetermined article is registered as the bundle - of - selling article , a cashier ( operating manager of terminal 11 ) discerns whether the article is a bundle - of - selling article , and whether the number of the article which is bought is the bundled article number . and if the bundle - of - selling is possible , the cashier operates the bundle - of - selling proclamation keys 57 in correspondence with the bundled article number . the cashier operates the bar code scanner 43 . the bar code data is read by the bar code scanner 43 . then , the bundled article number data is added , as a head figure , to the numerical row of the article code converted from bar code data . the bundled article number data is a data in correspondence with the bundle - of - selling proclamation keys 57 which are operated . thus , the article code for the bundle - of - selling is automatically framed . the selling registration transaction is performed in accordance with the article code which is framed . if the bundle - of - selling is impossible , a cashier seperates the bar code scanner 43 . the bar code data is read by the bar code scanner 43 . the selling registration transaction is performed in accordance with the article code which is converted from bar code data . for example , in the case of three chocolates bundled together bought by a customer , the cashier operates the three bundling key 57a , and the bar code scanner 43 . the bar code scanner 43 reads the bar code which is affixed on the chocolate . since the article code of the chocolate is [ 000000000001 ] ( first article code ), &# 34 ; 3 &# 34 ;, which is the bundled article number data , is additionally affixed at the head figure in the article code . thus [ 3000000000001 ] is framed as the article code for bundle - of - selling . the article information data of the article code which is framed is inquired to the file processor 13 . in this case , since [ 3000000000001 ] ( second article code ) is memorized in the article file 17 , the article information data in correspondence with [ 3000000000001 ] is received from file processor 13 . the article information data includes &# 34 ; bundled three chocolate &# 34 ; as the article name data and &# 34 ; 550 &# 34 ; ( bundle - of - selling price ) as the unit price data . the article information data is printed on receipt paper and displayed on the display section 33 . the article selling data is then transmitted to the file prosessor 13 . the article selling data ( selling data ) includes &# 34 ; 1 &# 34 ; as the sold article number data and &# 34 ; 550 &# 34 ; as the sold amount data . then &# 34 ; 1 &# 34 ; is added to the previously memorized total sold article number data in the total sold article number data area 17d in correspondence with [ 3000000000001 ] as the article code in the article file 17 . and &# 34 ; 550 &# 34 ; is added to the previously memorized total sold amount data in the total sold amount data area 17e in correspondence with [ 3000000000001 ] as the article code in the article file 17 . in case of one chocolate which is predetermined as the bundle - of - selling is bought by customer , the cashier operates the bar code scanner 43 . the bar code scanner 43 reads the bar code which is affixed on the chocolate . the article information data of the article code is inquired to the file processor 13 . since the article code read by the bar code scanner 43 is [ 000000000001 ], the article information data which includes &# 34 ; chocolate &# 34 ; as the article name data and &# 34 ; 200 &# 34 ; as the unit price is received from file processor 13 . the article information data is printed to the receipt paper and displayed at the display section 33 . and the article selling data which includes &# 34 ; 1 &# 34 ; as the sold article number data and &# 34 ; 200 &# 34 ; as the sold amount data is transmitted to the file prosessor 13 . then &# 34 ; 1 &# 34 ; is added to the previously memorized total sold article number data in the total sold article number data area 17d in correspondence with [ 000000000001 ] as the article code in the article file 17 , and &# 34 ; 200 &# 34 ; is added to the previously memorized total sold amount data in the total sold amount data area 17e in correspondence with [ 000000000001 ] as the article code in the article file 17 . according to this embodiment , it is possible to administer the article selling data of the predetermined article as the bundle - of - selling article , when it is sold as either an individual article unit or as a bundle - of - selling article by reducing the prices . further the cashier inputs the same article code when it is sold as either the bundle - of - selling or as an article unit , accordingly saving the cashier &# 39 ; s time . in this embodiment , three bundle - of - selling proclamation keys 57 are prepared in correspondence with the bundled article number . however , it is possible to input the bundled article number in combination with one bundle - of - selling proclamation key in combination with the numeric keys . in this embodiment , the bundled article number data is additionally affixed as the head figure in the article code when the article code for the bundle - of - selling is framed . however , the position where the bundled article number data is affixed is not restricted . other number data which is not related to the bundled article number data may be additionally affixed when the article code is framed . in this embodiment , the article code which is framed may have one more figure than the general article codes . however , it is possible to make the number of figures in the article code framed for bundled articles and the number of figures in the general article code equal by changing an unused figure to generate the bundled article number data . moreover , a counter for counting the number of each article which is inputted may be provided and the article code for the bundle - of - selling may be framed automatically when the number in the counter reaches the predetermined number . then the operation for performing the bundle - of - selling may be easier . the second embodiment will be described with reference to fig8 - 10 . the same reference numerals as in the first embodiment denote the same parts in the second embodiment , and a detailed description thereof will be omitted or simplified . the bundle - of - selling proclamation keys 57 are used in the first embodiment . however , the bundle - of - selling proclamation keys 57 are not used in the second embodiment . the number of articles purchased is inputted by the numeric keys 49 and the multiplication key 52 is operated and the bar code data is read by the bar code scanner 43 , when a plurality of the same article is sold . for example , when three chocolates are bought by a customer , the cashier operates the numeric keys 49 , multiplication key 52 and the bar code scanner 43 . &# 34 ; 3 &# 34 ; is inputted by the numeric keys 49 and the multiplication key 52 is operated and the bar code which is affixed on the chocolate is read by the bar code scanner 43 . when the multiplication key 52 is operated , the article code for the bundle - of - selling is framed . the article code in the article file 14 is then searched in accordance with the article code framed . if an article code which is the same as the article code framed is memorized in the article file 14 , the bundle - of - selling is performed . if an article code which is the same as article code framed is not memorized in the article file 14 , the multiplicative registration transaction is performed in accordance with the inputted article code . thus it is possible to administer the article selling data of the articles which are sold by the bundle - of - selling , even if the bundle - of - selling proclamation keys 57 are not provided in the product - selling - data processing apparatus . as compared with the first embodiment , the memory map shown in fig5 is changed to that shown in fig8 and a cpu 19 executes a flow chart in fig9 and fig1 in place of the processing shown in the flow chart of fig6 and fig7 . other arrangements and operation of the second embodiment are the same as those of the first embodiment . as shown in fig8 ram 23 includes an article code memory 65 for memorizing the article code inputted , a new article code memory 67 for memorizing the article code for the bundle - of - selling which is framed , a number data memory 69 for memorizing the number data which is inputted by the numeric keys 49 , and the multiplication flag data memory 71 for memorizing &# 34 ; 1 &# 34 ; as the multiplication flag data ( f ) which indicate the operation of the multiplication key 52 . the product - selling - data processing apparatus includes the function that the number data inputted by the operation of the numeric keys 49 is memorized into the number data memory 69 . the cpu 19 performs a transaction , as shown in fig9 when multiplication key 52 on the keyboard 29 is operated under the registration mode which has been selected by the mode switch 41 . the cpu 19 discerns whether the number data is memorized in the number data memory 69 . if the number data is memorized , &# 34 ; 1 &# 34 ; is established in the multiplication flag data memory 71 as the multiplication flag data ( f ). the cpu 19 further performs a transaction as shown in fig1 . in step st21 , bar code data , converted from an article code , which is generally attached to an article as a bar code label is read by bar code scanner 43 . the bar code data output from bar code scanner 43 is inversely converted to the article code ( in step st22 ) and the article code is memorized to the article code memory 59 ( in step st23 ). in step st24 , a status of the multiplication flag data ( f ) in the multiplication flag data memory 71 is examined . if &# 34 ; 1 &# 34 ; is memorized in the multiplication flag data memory 71 as the multiplication flag data ( f ), the yes - path is taken . otherwise , the no - path is taken . when the yes - path is taken in step st24 , an article code for the bundle - of - selling ( a third article code ) is framed based on the article code memorized in the article code memory 65 ( in step st25 ). ( framing means ) the article code for the bundle - of - selling is framed such that the number data memorized in the number data memory 69 is added , as a head figure , to the numerical row of the article code memorized in the article code memory 65 . in step st26 , the article code framed is memorized into the new article code memory 67 . in step st27 , the multiplication flag data ( f ) in the multiplication flag data memory 71 is cleared to &# 34 ; 0 &# 34 ;. in step st28 , the article information data , including an article name data , an article unit price data , which corresponds to the article code for the bundle - of - selling framed in step st25 is inquired from the pos terminal 11 to the file processor 13 . then the pos terminal 11 reseives a response from the file processor 13 . in step st29 , the response is examined in the pos terminal 11 . if the article information data is received , the yes - path is taken . otherwise , the no - path is taken . when the yes - path is taken in step st29 , the article selling data is obtained in accordance with the article information data . the article selling data includes a sold article number data and a sold amount data . the article selling data is transmitted to the file processor 13 . the article selling data is added to the previously memorized article selling data in the article file 17 ( in step st32 ). if the no - path is taken in step st24 or the no - path is taken in step st29 , the article information data , which corresponds to the article code memorized in the article code memory 65 is inquired from the pos terminal 11 to the file processor 13 ( in step st30 ). the pos terminal 11 receives , a response from the file processor 13 . in step st31 , the response is examined . if the article information data is received , the yes - path is taken . otherwise , the no - path is taken . when the yes - path is taken in step st31 , the multiplicative registration transaction is performed in the pos terminal 11 ( in step st32 ). the transaction of the file processor 13 is the same one of the first embodiment . according to the second embodiment , the article information data and the article selling data are memorized in article file 17 in correspondence with the article code of each article . so , for bundle - of - selling articles , the article information data and the article selling data are memorized in correspondence with the article code for the bundle - of - selling . the article code for the bundle - of - selling is framed by additionally affixing the number data at the head figure of the article code which is used by an article selling . the article name data and the unit price data are memorized as the article information data of each article . and the name data for the bundle - of - selling article and selling amount data are memorized as the article information data for the bundle - of - selling articles . since the bundle - of - selling proclamation keys 57 are not provided in the product - selling - data processing apparatus , it is possible to make the operation of the apparatus easier . the present invention has been described with respect to a specific embodiment . however , other embodiments based on the principles of the present invention should be obvious to those of ordinary skill in the art . such embodiments are intended to be covered by the claims .