Cod sursa(job #1685634)

Utilizator teodoramusatoiuTeodora Musatoiu teodoramusatoiu Data 11 aprilie 2016 19:39:49
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.77 kb
#include <iostream>
#include <fstream>

using namespace std;
ifstream in ("rmq.in");
ofstream out ("rmq.out");

const int N_max=100005;
const int L=17; //log2(N)=16,6..

int r[N_max][L+1], log[N_max],n,m,v[N_max],x,y,rez,lg;

int minim(int a,int b)
{
    if(a<b)
        return a;
    else
        return b;
}

int main()
{
    in>>n>>m;
    for(int i=1; i<=n; i++)
        in>>v[i];

    for(int i=1; i<=n; i++)
    {
        r[i][0]=v[i];
        for(int j=1; (1<<j)<=i; j++)
            r[i][j]=minim( r[i][j-1], r[i-(1<<(j-1))][j-1] );//
    }

    log[1]=0;
    for(int i=2; i<=n; i++)
        log[i]=1+log[i/2];

    for(int i=1; i<=m; i++)
    {
        in>>x>>y;
        lg=log[y-x+1];
        rez=minim( r[y][lg], r[ x+(1<<lg)-1 ][lg] );
        out<<rez<<'\n';
    }
    return 0;
}