Compilare: user.cpp: In function ‘void read()’: user.cpp:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void make_pairing()’: user.cpp:44: warning: comparison between signed and unsigned integer expressions user.cpp:49: warning: comparison between signed and unsigned integer expressions user.cpp:68: warning: comparison between signed and unsigned integer expressions user.cpp:69: warning: comparison between signed and unsigned integer expressions user.cpp:73: warning: comparison between signed and unsigned integer expressions user.cpp:79: warning: comparison between signed and unsigned integer expressions user.cpp:82: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void ciclu_euler()’: user.cpp:125: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:168: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:169: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:170: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result