Compilare: user.cpp: In function ‘int BellmanFord()’: user.cpp:87:49: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < V[ x ].size(); i++) { ^ user.cpp: In function ‘void read()’: user.cpp:35:42: 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:37:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:45:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x, &y, &c); ^ user.cpp: In function ‘void solve()’: user.cpp:55:43: 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); ^