Pagini recente » Cod sursa (job #290062) | Cod sursa (job #2097467) | Cod sursa (job #1615473) | Cod sursa (job #3288854) | Cod sursa (job #1588369)
#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("stramosi.in");
ofstream g("stramosi.out");
vector <int> v[250005],l[250005],pos[250005];
int n,q,a[250005],k,sol[250005],use[250005],lft[250005],ok;
void DF(int x)
{ int i;
k=0; k++; a[k]=x;
lft[1]=-1;
while(k)
{ x=a[k]; use[x]=1;
for(i=0;i<l[x].size();i++)
if (l[x][i]<=k-1) sol[pos[x][i]]=a[k-l[x][i]];
ok=0;
for(i=lft[k]+1;i<v[x].size();i++)
if (!use[v[x][i]])
{ lft[k]=i;
k++; a[k]=v[x][i];
lft[k]=-1;
ok=1;
break;
}
if (!ok) k--;
}
}
int main()
{ int i,x,y;
f>>n>>q;
for(i=1;i<=n;i++)
{ f>>x;
v[i].push_back(x);
v[x].push_back(i);
}
for(i=1;i<=q;i++)
{ f>>x>>y;
l[x].push_back(y);
pos[x].push_back(i);
}
for(i=1;i<=n;i++)
if (!use[i]) DF(i);
for(i=1;i<=q;i++)
g<<sol[i]<<"\n";
return 0;
}