Cod sursa(job #1214746)

Utilizator MaarcellKurt Godel Maarcell Data 31 iulie 2014 12:01:22
Problema Range minimum query Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <fstream>
#include <iostream>
using namespace std;

int N,M,segtree[1000000],a[100000],ql,qr,MIN;

void build_tree(int nod, int l, int r){
    if (l==r){
        segtree[nod]=a[l];
        return;
    }

    int mid=(l+r)/2;
    build_tree(nod*2,l,mid);
    build_tree(nod*2+1,mid+1,r);
    segtree[nod]=min(segtree[nod*2],segtree[nod*2+1]);
}

void query(int nod, int l, int r){
    if (ql<=l && r<=qr){
        MIN=min(MIN,segtree[nod]);
        return;
    }

    int mid=(l+r)/2;
    if (ql<=mid) query(nod*2,l,mid);
    if (mid<qr) query(nod*2+1,mid+1,r);
}
int main(){
    ifstream in("rmq.in");
    ofstream out("rmq.out");
    in>> N >> M;

    int i;
    for (i=1; i<=N; i++)
        in >> a[i];

    build_tree(1,1,N);

    for (i=1; i<=M; i++){
        in >> ql >> qr;
        MIN=1000000;
        query(1,1,N);
        out << MIN << "\n";
    }
    return 0;
}