Cod sursa(job #1238820)

Utilizator acomAndrei Comaneci acom Data 7 octombrie 2014 19:58:31
Problema Stramosi Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.66 kb
#include<cstdio>
using namespace std;
#define NMAX 250005
int n,m,p,q,P[NMAX],A[20][NMAX];
int stramos(int x, int y)
{
    if (!y || !x)
        return x;
    return stramos(A[P[y&-y]][x],y&(y-1));
}
int main()
{
    int i,j;
    freopen("stramosi.in","r",stdin);
    freopen("stramosi.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=1;i<=n;++i)
        scanf("%d",&A[0][i]);
    for (i=2;i<=n;++i)
        P[i]=1+P[i>>1];
    for (i=1;(1<<i)<=(n<<1);++i)
        for (j=1;j<=n;++j)
            A[i][j]=A[i-1][A[i-1][j]];
    for (i=0;i<m;++i)
    {
        scanf("%d%d",&q,&p);
        printf("%d\n",stramos(q,p));
    }
    return 0;
}