Compilare: user.cpp: In function ‘void citire()’: user.cpp:16: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void scriere()’: user.cpp:29: warning: comparison between signed and unsigned integer expressions user.cpp:31: warning: comparison between signed and unsigned integer expressions user.cpp:27: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp: In function ‘void dfs(int)’: user.cpp:56: warning: comparison between signed and unsigned integer expressions