Compilare: user.cpp: In function ‘int main()’: user.cpp:84: warning: statement has no effect user.cpp:80: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:81: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:83: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:88: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void back(int, int, int, int)’: user.cpp:10: warning: ‘pmin’ may be used uninitialized in this function user.cpp:10: warning: ‘i’ may be used uninitialized in this function