Cod sursa(job #2894389)

Utilizator David_PatranjelDavid Patranjel David_Patranjel Data 27 aprilie 2022 19:35:02
Problema Range minimum query Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.25 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("rmq.in");
ofstream fout("rmq.out");
int main()
{
    int v[1000],n,m,minima[100][100],log2[1000];
    fin>>n>>m;
    for(int i = 1; i <= n; i++){
        fin>>v[i];
        minima[0][i] = v[i];
    }
    log2[1] = 0;
    for(int i = 2; i <=n; i++){
        log2[i] = log2[i/2]+1;
    }
    /*
    cout<<n<<" "<<m<<endl;
    for(int i = 0; i <= n-1; i++)
        cout<<v[i]<<" ";
    cout<<endl;*/
    ///RMQ
    for(int j = 1; (1<<j) <= n; j++){
        for(int i = 1; i-1+(1<<j) <= n; i++){
            minima[j][i] = min(minima[j-1][i], minima[j-1][i+(1<<(j-1))]);
        }
    }
    /*
    for(int i = 0; i <= n; i++){
        for( int j = 0; j <= n; j++){
            cout<<minima[i][j]<<" ";
        }
        cout<<endl;
    }*/
    ///Rezolvarea query-urilor - O(1)
    for(int i = 1; i <= m; i++){
        int x,y;
        fin>>x>>y;
        if(y<x) swap(x,y);
        int lungime = y-x+1;
        int aux = log2[lungime];
        ///cout<<x<<" "<<y<<" "<<aux<<" "<<min(minima[aux][x], minima[aux][y-(1<<aux)+1])<<endl;
        fout<<min(minima[aux][x], minima[aux][y-(1<<aux)+1])<<endl;
    }

    fin.close();
    fout.close();
    return 0;
}