Cod sursa(job #3322852)

Utilizator pepsiM4A1Ozturk Arif pepsiM4A1 Data 15 noiembrie 2025 22:45:44
Problema Stramosi Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.54 kb
#include<cstdio>
using namespace std;
const int DIM=10000;
int poz=DIM-1;
char buff[DIM];
void citeste(int &nr)
{
    while(!('0'<=buff[poz]&&buff[poz]<='9'))
    {
        if(++poz==DIM)
        {
            fread(buff,1,DIM,stdin);
            poz=0;
        }
    }
    while(('0'<=buff[poz]&&buff[poz]<='9'))
    {
        nr=nr*10 + buff[poz]-'0';
        if(++poz==DIM)
        {
            fread(buff,1,DIM,stdin);
            poz=0;
        }
    }
}

const int NMAX = 250005;
const int LOG_MAX = 20;
int stramosi[LOG_MAX][NMAX]; 



void ComputeStramosi(const int &n) {
    for (int j = 1; j <= 18; j++) {
        for (int i = 1; i <= n; i++) {
            stramosi[j][i] = stramosi[j - 1][stramosi[j - 1][i]];
        }
    }
}
int MSB(const int &x) {
    return 31 - __builtin_clz(x);
}
int query(const int &q, int &p) {
    int stramos = q;
    while (p != 0) {
        if (stramos == 0) {
            break;
        }

        int jump_positions = MSB(p);
        stramos = stramosi[jump_positions][stramos];
        p -= (1 << jump_positions);
    }
    return stramos;
}

int main() {
    freopen("stramosi.in", "r", stdin);
    freopen("stramosi.out", "w", stdout);

    int n, queries;
    citeste(n);
    citeste(queries);

    for (int i = 1; i <= n; i++) {
        citeste(stramosi[0][i]);
    }

    ComputeStramosi(n);

    int q, p;
    for (; queries > 0; queries--) {
        citeste(q);
        citeste(p);
        printf("%d\n", query(q, p));
    }

    return 0;
}