Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:14:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<g[x].size();i++) ^ user.cpp: In function ‘void dfss(int)’: user.cpp:21:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<gt[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:42:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<sol[i].size();j++) printf("%d ",sol[i][j]); ^ user.cpp:25:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in","r",stdin); ^ user.cpp:26:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out","w",stdout); ^ user.cpp:27:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:29:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^