Compilare: user.cpp: In function ‘bool bfs()’: user.cpp:35:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < graph[x].size();i++) ^ user.cpp: In function ‘int max_flow()’: user.cpp:57:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < graph[n].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:87:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxflow.in","r",stdin); ^ user.cpp:88:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxflow.out","w",stdout); ^ user.cpp:90:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:95:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&x,&y,&z); ^