Compilare: user.cpp: In function ‘bool iugo(int)’: user.cpp:26:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[node].size();i++) ~^~~~~~~~~~~~~~~ user.cpp:36:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[node].size();i++) ~^~~~~~~~~~~~~~~ user.cpp: In function ‘int pairing()’: user.cpp:66:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘void scan()’: user.cpp:10:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "cuplaj.in", "r", stdin ); ^ user.cpp:11:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "cuplaj.out", "w", stdout ); ^ user.cpp:12:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&N,&M,&E); ^ user.cpp:15:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&u,&v); ^