Compilare: user.cpp: In function ‘void first_dfs(int)’: user.cpp:14:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<g[node].size();i++) ^ user.cpp: In function ‘void second_dfs(int)’: user.cpp:25:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<gt[node].size();i++) ^ user.cpp: In function ‘void topological_sort(int)’: user.cpp:48:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<graph[node].size();i++) ^ user.cpp: In function ‘void compute(std::vector<int>, std::vector<int>*, int)’: user.cpp:55:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size();i++) ^ user.cpp:57:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size();i++){ ^ user.cpp:60:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<now[v[i]].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:88:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<component[i].size();j++){ ^ user.cpp:68:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drumuri5.in","r",stdin); ^ user.cpp:69:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drumuri5.out","w",stdout); ^ user.cpp:71:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:73:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^