Cod sursa(job #1464371)

Utilizator Liviu98Dinca Liviu Liviu98 Data 23 iulie 2015 10:54:03
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.85 kb
#include <iostream>
#include <stdio.h>
#include <algorithm>
#define NMax 100009
#define LgMax 21
using namespace std;
int v[NMax],lg[NMax],RMQ[LgMax][NMax],N,Q,x,y;

void Build()
{
    for(int i=2;i<=N;i++)
        lg[i]=lg[i/2]+1;

    for(int j=1;j<=N;j++)
        RMQ[0][j]=v[j];

    for(int i=1;(1<<i)<=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))]);
}

int Query(int& x,int& y)
{
    if(x>y)
        swap(x,y);
    int i=lg[y-x+1];
    return min(RMQ[i][x],RMQ[i][y-(1<<i)+1]);
}

int main()
{
    freopen("rmq.in","r",stdin);
    freopen("rmq.out","w",stdout);

    scanf("%d%d",&N,&Q);
    for(int i=1;i<=N;i++)
       scanf("%d",&v[i]);

    Build();

    for(int i=1;i<=Q;i++)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",Query(x,y));
    }
}