Compilare: user.cpp: In function ‘int main()’: user.cpp:39:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < v[j].size(); ++k) ^ user.cpp:49:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int t = 0; t < v[0].size(); ++t) ^ user.cpp:16:39: 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:17:41: 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:18:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:24:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^