Compilare: user.cpp: In function ‘void make_per()’: user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void euler(int, int, int)’: user.cpp:76: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:121: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:122: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result