Compilare: user.cpp: In function ‘int main()’: user.cpp:46:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( k = 0 ; k < g[j].size() ; ++k ) ^ user.cpp:50:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0 ; i < g[0].size() ; ++i) ^ user.cpp:24:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.in","r",stdin); ^ user.cpp:25:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.out","w",stdout); ^ user.cpp:27:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:38:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ user.cpp:40:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&cost[x][y]); ^