Cod sursa(job #1059203)

Utilizator mads2194FMI - Andrei Stroe mads2194 Data 16 decembrie 2013 13:17:49
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.28 kb
#include <cstdio>
#include <algorithm>

#define N 100001

using namespace std;

int v[N],T[4*N];
int n;

void create(int st=1,int dr=n,int nod=1)
{
    if(st==dr)
    {
        T[nod] = v[st];
        return ;
    }
    create(st,(st+dr)/2,nod*2);
    create((st+dr)/2+1,dr,nod*2+1);
    T[nod] = max(T[nod*2],T[nod*2+1]);

}

void update(int val,int pos,int st=1,int dr=n,int nod=1)
{
    if(st==dr)
    {
        T[nod]=val;
        return ;
    }
    if(pos<=(st+dr)/2)
        update(val,pos,st,(st+dr)/2,nod*2);
    else
        update(val,pos,(st+dr)/2+1,dr,nod*2+1);
    T[nod] = max(T[nod*2],T[nod*2+1]);
}

int getmax(int a,int b,int st=1,int dr=n,int nod=1)
{
    if(a>dr) return 0;
    if(b<st) return 0;
    if(a<=st && dr<=b) return T[nod];
    return max( getmax(a,b,st,(st+dr)/2,nod*2), getmax(a,b,(st+dr)/2+1,dr,nod*2+1) );
}

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

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

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