In this problem, we consider a simple programming language that has only declarations of one- dimensional integer arrays and assignment statements. The problem is to find a bug in the given program.

The syntax of this language is given in BNF as follows:

<image>

where <new line> denotes a new line character (LF).

Characters used in a program are alphabetical letters, decimal digits, =, [, ] and new line characters. No other characters appear in a program.

A declaration declares an array and specifies its length. Valid indices of an array of length n are integers between 0 and n - 1, inclusive. Note that the array names are case sensitive, i.e. array a and array A are different arrays. The initial value of each element in the declared array is undefined.

For example, array a of length 10 and array b of length 5 are declared respectively as follows.


a[10]
b[5]


An expression evaluates to a non-negative integer. A <number> is interpreted as a decimal integer. An <array_name> [<expression>] evaluates to the value of the <expression> -th element of the array. An assignment assigns the value denoted by the right hand side to the array element specified by the left hand side.

Examples of assignments are as follows.


a[0]=3
a[1]=0
a[2]=a[a[1]]
a[a[0]]=a[1]


A program is executed from the first line, line by line. You can assume that an array is declared once and only once before any of its element is assigned or referred to.

Given a program, you are requested to find the following bugs.

* An index of an array is invalid.
* An array element that has not been assigned before is referred to in an assignment as an index of array or as the value to be assigned.



You can assume that other bugs, such as syntax errors, do not appear. You can also assume that integers represented by <number>s are between 0 and 231 - 1 (= 2147483647), inclusive.



Input

The input consists of multiple datasets followed by a line which contains only a single '.' (period). Each dataset consists of a program also followed by a line which contains only a single '.' (period). A program does not exceed 1000 lines. Any line does not exceed 80 characters excluding a new line character.

Output

For each program in the input, you should answer the line number of the assignment in which the first bug appears. The line numbers start with 1 for each program. If the program does not have a bug, you should answer zero. The output should not contain extra characters such as spaces.

Example

Input

a[3]
a[0]=a[1]
.
x[1]
x[0]=x[0]
.
a[0]
a[0]=1
.
b[2]
b[0]=2
b[1]=b[b[0]]
b[0]=b[1]
.
g[2]
G[10]
g[0]=0
g[1]=G[0]
.
a[2147483647]
a[0]=1
B[2]
B[a[0]]=2
a[B[a[0]]]=3
a[2147483646]=a[2]
.
.


Output

2
2
2
3
4
0
                            #include <bits/stdc++.h>
                            #include<iostream>
                            #include<cstdio>
                            #include<vector>
                            #include<queue>
                            #include<map>
                            #include<cstring>
                            #include<string>
                            #include <math.h>
                            #include<algorithm>
                        //    #include <boost/multiprecision/cpp_int.hpp>
                            #include<functional>
                    #define int long long
                            #define inf  1000000007
                            #define pa pair<int,int>
                            #define ll long long
                            #define pal pair<double,pa>
                            #define ppa pair<pa,pa>
                            #define ppap pair<int,pa>
                            #define ssa pair<string,int>
                            #define  mp make_pair
                            #define  pb push_back
                            #define EPS (1e-10)
                            #define equals(a,b) (fabs((a)-(b))<EPS)
                     
                            using namespace std;
                  
                            class Point{
                            	public:
                            	double x,y;
                            	Point(double x=0,double y=0):x(x),y(y) {}
                            	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                            	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                            	Point operator * (double a) {return Point(x*a,y*a);}
                            	Point operator / (double a) {return Point(x/a,y/a);}
                            	double absv() {return sqrt(norm());}
                            	double norm() {return x*x+y*y;}
                            	bool operator < (const Point &p) const{
                            		return x != p.x ? x<p.x: y<p.y;
                            	}
                            	bool operator == (const Point &p) const{
                            		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                            	}
                            };
                            typedef Point Vector;
                     
                            struct Segment{
                            Point p1,p2;
                            };
                             double dot(Vector a,Vector b){
                            	return a.x*b.x+a.y*b.y;
                            }
                            double cross(Vector a,Vector b){
                            	return a.x*b.y-a.y*b.x;
                            }
                        
bool parareru(Point a,Point b,Point c,Point d){
//	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
	return abs(cross(a-b,d-c))<EPS;
}
double distance_ls_p(Point a, Point b, Point c) {
  if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
  if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
  return abs(cross(b-a, c-a)) / (b-a).absv();
}
bool is_intersected_ls(Segment a,Segment b) {
	if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return false;
	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){
//		cout<<"sss"<<endl;
		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
		return false;
	}
  else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
}

double segment_dis(Segment a,Segment b){
	if(is_intersected_ls(a,b))return 0;
	double r=distance_ls_p(a.p1, a.p2, b.p1);
	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
	return r;
}
Point intersection_ls(Segment a, Segment b) {
  Point ba = b.p2-b.p1;
  double d1 = abs(cross(ba, a.p1-b.p1));
  double d2 = abs(cross(ba, a.p2-b.p1));
  double t = d1 / (d1 + d2);

  return a.p1 + (a.p2-a.p1) * t;
}

                string itos( int i ) {
                ostringstream s ;
                s << i ;
                return s.str() ;
                }
                 
                int gcd(int v,int b){
                	if(v>b) return gcd(b,v);
                	if(v==b) return b;
                	if(b%v==0) return v;
                	return gcd(v,b%v);
                }
 
                double distans(double x1,double y1,double x2,double y2){
                	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                	return sqrt(rr);
                	
                }
                /*
int pr[100010];
//int inv[100010];
*/ 
int beki(int wa,int rr,int warukazu){
	if(rr==0) return 1ll;
	if(rr==1) return wa%warukazu;
	if(rr%2==1) return (beki(wa,rr-1,warukazu)*wa)%warukazu;
	int zx=beki(wa,rr/2,warukazu);
	return (zx*zx)%warukazu;
}
  /*
void gya(){
	pr[0]=1;
	for(int i=1;i<100010;i++){
		pr[i]=(pr[i-1]*i)%inf;
	}
	for(int i=0;i<100010;i++) inv[i]=beki(pr[i],inf-2);
	
}

*/

                         //----------------kokomade tenpure------------
map<int,int> ma[60];
string s;
int kosuu[60]={0};

map<char,int> ch;
bool ok;
int suuji(int i){
//	cout<<s<<" "<<i<<" "<<s[i]<<endl;
	int d=0;
	while(1){
		d*=10;
		d += s[i]-'0';
		i++;
		if(s[i]<'0'|| s[i]>'9') break;
	}
	return d;
}

void sengen(){
	
	kosuu[ch[s[0]]]=suuji(2);
	return;
}


int value(int hi,int mi){
	bool b=true;
	for(int i=hi;i<=mi;i++)if(!isdigit(s[i]))b=false;
	
	if(b) return suuji(hi);
	
	int z=value(hi+2,mi-1);
	int ban=ch[s[hi]];
	if(kosuu[ban]<=z) ok=0;
	if(ma[ban].find(z)==ma[ban].end()) ok=0;
	return ma[ban][z];
}


void tuika(int eq){
	
	int r=value(eq+1,s.length()-1);
	int er=value(2,eq-2);
//	cout<<r<<" "<<er<<endl;
	if(ok==0) return;
	
	if(kosuu[ch[s[0]]]<=er){
		ok=0;
		return;
	}
	ma[ch[s[0]]][er]=r;
	return;
	
}



signed main(){
	
	for(char c='a';c<='z';c++) ch[c]= c-'a';
	for(char c='A';c<='Z';c++) ch[c]= c-'A'+30;
	
	
	while(1){
	//string s;
	cin>>s;
		if(s==".") break;
		
		for(int i=0;i<60;i++){
			ma[i].clear();
			kosuu[i]=0;
		}
		int owari=0;
		ok=true;
		int ans=1;
		while(s!="."){
			
			int eq=-1;
			for(int i=0;i<s.length();i++)if(s[i]=='=')eq=i;
			if(eq==-1){
				
				sengen();
				
				
			}
			else{
				
				
				tuika(eq);
				
			}
			
			
			
			
			if(!ok && owari==0){
				cout<<ans<<endl;
				owari=1;
			//	break;
			}
			ans++;
			cin>>s;
		}
		if(ok) cout<<0<<endl;

	}
	return 0;
}