Compilare: main.cpp: In function 'void dfsup(int)': main.cpp:22:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();i++) dfsup(v[nod][i]); ~^~~~~~~~~~~~~~ main.cpp: In function 'void dfs(int)': main.cpp:28:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void dfsdown(int, int)': main.cpp:39:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp:41:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp:44:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp:48:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0,k=minn[vec];j<g[vec].size();j++,k++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:62:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("meow.in","r",stdin); ^ main.cpp:63:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("meow.out","w",stdout); ^ main.cpp:65:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&l,&q); ^ main.cpp:68:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ main.cpp:71:46: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] for(int i=0;i<n;i++) {scanf("%d",&val[i]);newval[i]=val[i];} ^ main.cpp:82:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ main.cpp:64:15: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized] int n,q,x,sol,ans=0; ^~~