Cod sursa(job #1638959)

Utilizator bt.panteaPantea Beniamin bt.pantea Data 8 martie 2016 10:18:25
Problema Range minimum query Scor 80
Compilator cpp Status done
Runda Arhiva educationala Marime 1.35 kb
#include <iostream>
#include <fstream>
#define MAX 100005
using namespace std;
ifstream f ("rmq.in");
ofstream g ("rmq.out");
int MinArb[100*MAX],n,m,x,Val,Pos,Start,Finish,minim,a,b;

int min (int a, int b)
{
    if (a==0) return b;
    else if (b==0) return a;
    else if (a<b) return a;
    else return b;
}
void Update(int nod, int left, int right)
{
    if (left==right)
    {
        MinArb[nod]=Val;
        return;
    }

    int div=(left+right)/2;
    if (Pos<=div) Update(2*nod,left, div);
    else Update(2*nod+1, div+1,right);

    //if (MinArb[2*nod]) MinArb[nod]=MinArb[2*nod];
    //if (MinArb[2*nod+1] && MinArb[nod] > MinArb[2*nod+1]) MinArb[nod]=MinArb[2*nod+1];
    MinArb[nod]=min(MinArb[2*nod],MinArb[2*nod+1]);
}
void Query(int nod, int left, int right)
{
    if (left>=Start && right <= Finish)
    {
        minim=min(MinArb[nod],minim);
        return;
    }
    int div=(left+right)/2;
    if (Start <= div) Query(2*nod, left, div);
    if (div < Finish) Query(2*nod+1,div+1,right);
}
int main()
{
    f>>n>>m;

    for (int i=1;i<=n;i++)
    {
        f>>x;
        Pos=i;
        Val=x;
        Update(1,1,n);
    }
    for (int i=1;i<=m;i++)
    {
        f>>a>>b;
        minim=1000000;
        Start=a;
        Finish=b;
        Query(1,1,n);
        g<<minim<<'\n';
    }
    return 0;
}