Cod sursa(job #848221)

Utilizator Al3ks1002Alex Cociorva Al3ks1002 Data 5 ianuarie 2013 00:23:43
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 0.93 kb
#include<cstdio>
#include<algorithm>
using namespace std;
int i,n,m,op,a,b,arb[1<<18],poz,val;
void update(int nod,int st,int dr)
{
    if(st==dr)
    {
        arb[nod]=val;
        return;
    }
    int mi=(st+dr)/2;
    if(poz<=mi) update(2*nod,st,mi);
    else update(2*nod+1,mi+1,dr);
    arb[nod]=max(arb[2*nod],arb[2*nod+1]);
}
int query(int nod,int st,int dr)
{
    if(st>=a && dr<=b) return arb[nod];
    int mi=(st+dr)/2,X=0,Y=0;
    if(a<=mi) X=query(2*nod,st,mi);
    if(b>mi) Y=query(2*nod+1,mi+1,dr);
    return max(X,Y);
}
int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
    {
        scanf("%d",&val);
        poz=i; update(1,1,n);
    }
    for(;m;m--)
    {
        scanf("%d%d%d",&op,&a,&b);
        if(!op) printf("%d\n",query(1,1,n));
        else {poz=a; val=b; update(1,1,n);}
    }
    return 0;
}