Compilare: user.cpp: In member function ‘bool cmp::operator()(const int&, const int&)’: user.cpp:25: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int comp(int, int)’: user.cpp:46: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:118: warning: comparison between signed and unsigned integer expressions user.cpp:76: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:77: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:78: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:81: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:84: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:96: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result /tmp/ccl0U3I1.o: In function `main': user.cpp:(.text+0x42f): warning: the `gets' function is dangerous and should not be used.