Compilare: main.cpp: In function 'void dfs(int)': main.cpp:12:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void dfs1(int)': main.cpp:25:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<g[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:33:32: 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); ^ main.cpp:34:34: 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); ^ main.cpp:36:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:40:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^