Compilare: main.cpp: In function 'int main()': main.cpp:56:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=2;i<=lca.size();i++) lg[i]=lg[i/2]+1; ~^~~~~~~~~~~~ main.cpp:57:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<lca.size();i++) sol[0].push_back(i); ~^~~~~~~~~~~ main.cpp:58:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1,x=2;x<=lca.size();i++,x<<=1) ~^~~~~~~~~~~~ main.cpp:42:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pirati.in", "r", stdin); ^ main.cpp:43:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pirati.out", "w", stdout); ^ main.cpp:44:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n",&n,&m,&q); ^ main.cpp:45:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=n;i++) scanf("%s\n",v[i]+1); ^ main.cpp:67:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x,&y,&x2,&y2); ^