Compilare: user.cpp: In function ‘int main()’: user.cpp:52: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:53: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:55: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:57: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:61: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void op2(int)’: user.cpp:38: warning: ‘mij’ may be used uninitialized in this function user.cpp: In function ‘void op1(int)’: user.cpp:24: warning: ‘mij’ may be used uninitialized in this function user.cpp: In function ‘void op0(int)’: user.cpp:7: warning: ‘mij’ may be used uninitialized in this function