what is the purpose of int3 in the program
INT (x86 instruction) The INT 3 instruction is defined for use by debuggers to temporarily replace an instruction in a running program in order to set a breakpoint. Other INT instructions are encoded using two bytes. This makes them unsuitable for use in patching instructions (which can be one byte long); see SIGTRAP.
MP3 MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III)[4] is an audio coding format for digital audio. Originally defined as the third audio format of the MPEG-1 standard, it was retained and further extended—defining additional bit rates and support for more audio channels—as the third audio format of the subsequent MPEG-2 standard. A third version, known as MPEG 2.5—extended to better support lower bit rates—is commonly implemented, but is not a recognized standard.