Compilare: user.cpp: In function ‘int main()’: user.cpp:41:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int par=0;par<inc[pas].size();par++) ~~~^~~~~~~~~~~~~~~~ user.cpp:16:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin); ^ user.cpp:17:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.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:21:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&pos1,&pos2,&l); ^