Cod sursa(job #2007037)

Utilizator Vlad_lsc2008Lungu Vlad Vlad_lsc2008 Data 1 august 2017 18:17:49
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.76 kb
#include <iostream>
#include <fstream>
using namespace std;

int n,m,rmq[100010][20],x[100010],lg[100010];

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

int main()
{
    int i,j;
    ifstream t1("rmq.in");
    ofstream t2("rmq.out");
    t1>>n>>m;
    for(i=1;i<=n;i++) t1>>x[i];

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

    for(i=1;i<=n;i++) rmq[i][0]=x[i];

    for(j=1; (1<<j) <=n; j++)
        for(i=1; i+(1<<j)-1<=n ;i++)
            rmq[i][j]=minim( rmq[i][j-1], rmq[i + (1<< (j-1)) ][j-1] );

    int a,b,l;
    for(i=1;i<=m;i++)
    {
        t1>>a>>b;
        l=lg[b-a+1];
        t2<<minim( rmq[a][l], rmq[ b- (1<<l) +1 ][l] )<<'\n';
    }
    t1.close();
    t2.close();
    return 0;
}