Compilare: main.cpp:2:89: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] 2 | int n,m,v[1<<18],i,x,y,k;std::ifstream f("stramosi.in");std::ofstream g("stramosi.out");main(){for(f>>n>>m;i<n;f>>v[++i],k+=(v[i]==i-1));if(k==n)while(f>>x>>y)g<<(x>=y?x-y:0)<<'\n';else while(f>>x>>y)for(;x&&y--;x=v[x],g<<x<<'\n');} | ^~~~