Cod sursa(job #1495672)

Utilizator andreeacozma95Cozma Andreea andreeacozma95 Data 3 octombrie 2015 13:12:48
Problema Arbori de intervale Scor 100
Compilator c Status done
Runda Arhiva educationala Marime 1.21 kb
#include <stdio.h>
#include <stdlib.h>
#define MAX(a,b) (a>b)?a:b
int arbore[262145]; //simulez arbore complet
int n,m;

void update(int i,int st, int dr, int a,int b,int val)
{
    if (a<=st && dr<=b)
        arbore[i]=val;
    else
    {
        int m=(st+dr)/2;
        if (a<=m)
            update(i*2,st,m,a,b,val);
        if (m<b)
            update(i*2+1,m+1,dr,a,b,val);
        arbore[i]=MAX(arbore[i*2],arbore[i*2+1]);
    }
}

int query (int i,int st, int dr, int a, int b)
{

    if (a<=st && dr<=b)
        return arbore[i];
    else
    {
        int max1=0,max2=0;
        int m=(st+dr)/2;
        if (a<=m)
            max1=query(i*2,st,m,a,b);
        if (m<b)
            max2=query(i*2+1,m+1,dr,a,b);
        return MAX(max1,max2);
    }
}

int main()
{
    int i,t,a,b;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);

    scanf ("%d%d",&n,&m);
    for (i=1;i<=n;i++)
    {
        scanf("%d",&a);
        update(1,1,n,i,i,a);
    }

    for (i=0;i<m;i++)
    {
        scanf("%d%d%d",&t,&a,&b);
        if (t==0)
            printf("%d\n",query(1,1,n,a,b));
        else
            update(1,1,n,a,a,b);
    }
    return 0;
}