Pagini recente » Cod sursa (job #829619) | Cod sursa (job #2272044) | Cod sursa (job #2363714) | Cod sursa (job #2800045) | Cod sursa (job #2280262)
#include <fstream>
using namespace std;
ifstream fin("stramosi.in");
ofstream fout("stramosi.out");
const int NMax = 250000;
int A[20][NMax + 5],Log2[NMax + 5];
int N,M;
void Read()
{
fin >> N >> M;
for(int i = 1; i <= N; ++i)
fin >> A[0][i];
}
void Precalculate()
{
for(int i = 2; i <= N; ++i)
Log2[i] = Log2[i/2] + 1;
for(int i = 1; (1<<i) <= N; ++i)
for(int j = 1; j <= N; ++j)
A[i][j] = A[i-1][A[i-1][j]];
}
int Ancestor(int Q, int P)
{
while(P)
{
int K = Log2[P];
Q = A[K][Q];
P = P - (1<<K);
}
return Q;
}
void SolveAndPrint()
{
while(M--)
{
int Q,P;
fin >> Q >> P;
fout << Ancestor(Q,P) << "\n";
}
}
int main()
{
Read();
Precalculate();
SolveAndPrint();
return 0;
}