Cod sursa(job #2731122)

Utilizator ililogIlinca ililog Data 27 martie 2021 12:42:46
Problema Range minimum query Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.1 kb
using namespace std;
#include<bits/stdc++.h>

int rmq[18][100002];
int n,m;
int a[100002];
int lg[100002];
int l;

int main() {

    ifstream fin("rmq.in");
    ofstream fout("rmq.out");
    
    fin >> n >> m;
    
    for (int i = 1; i<=n; i++) {
        fin >> rmq[0][i];
    }
    
    lg[1] = 0;
    //cout << '0';
    for (int i = 2; i<=n; i++) {
        lg[i] = lg[i/2]+1;
        //cout << " " << lg[i];
    }
    //cout << endl;
    
    for (int i = 1; i <= lg[n]; i++) {
        for (int j = 1; j<= n - (1<<i)+1; j++) {
            rmq[i][j] = min(rmq[i-1][j], rmq[i-1][j+(1<<(i-1))]);
        }
    }
    /*
    for (int i = 0; (1<<i) <= n; i++) {
        for (int j = 1; j<=n-(1<<i)+1; j++) {
            cout << rmq[i][j] << " ";
        }
        cout << endl;
    }
    */
    int x,y, diff, sh;
    
    for (int i = 1; i<=m; i++) {
        fin >> x >> y;
        
        diff = y-x+1;
        l = lg[diff];
        sh = diff - (1<<l);
        fout << min(rmq[l][x], rmq[l][x+sh]) << endl;
    }
    
    fin.close();
    fout.close();

    return 0;
}