Cod sursa(job #3225470)

Utilizator maiaauUngureanu Maia maiaau Data 17 aprilie 2024 17:41:52
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.82 kb
#include <bits/stdc++.h>
using namespace std;
using pii = pair<int,int>;
using ll = long long;
#define pb push_back

ifstream fin("rmq.in");
ofstream fout("rmq.out");

const int N = 1e5+3;

int n, m, rmq[18][N], query(int,int);

int main()
{
    fin.tie(0); fout.tie(0);
    ios_base::sync_with_stdio(0);
    
    fin >> n >> m;
    for (int i = 1; i <= n; i++)
        fin >> rmq[0][i];
    for (int lg = 2, h = 1; lg <= n; lg *= 2, h++)
        for (int i = 1; i + lg - 1 <= n; i++)
            rmq[h][i] = min(rmq[h-1][i], rmq[h-1][i+lg/2]);

    while (m--){
        int x, y; fin >> x >> y;
        if (x > y) swap(x, y);
        fout << query(x, y) << '\n';
    }

    return 0;
}

int query(int l, int r){
    int lg = r - l + 1;
    int pw = 31 - __builtin_clz(lg);
    return min(rmq[pw][l], rmq[pw][r-(1<<pw)+1]);
}

//17:35