Compilare: user.cpp: In function ‘int bellmanford(long long int)’: user.cpp:33:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<v[x].size();j++) { ^ user.cpp: In function ‘int main()’: user.cpp:55:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,a,b,c; ^ user.cpp:52:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclu.in","r",stdin); ^ user.cpp:53:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclu.out","w",stdout); ^ user.cpp:54:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:57:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&a,&b,&c); ^