Cod sursa(job #1348220)

Utilizator ionutpop118Pop Ioan Cristian ionutpop118 Data 19 februarie 2015 16:17:43
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.13 kb
#include<cstdio>
#include<algorithm>
using namespace std;
int ans;
int  aint[600005];
void update(int nod,int st,int dr,int i,int p)
{
    if(st==dr)
    {
        aint[nod]=p;
        return;
    }
    int med=(st+dr)/2;
    if(i<=med)
        update(2*nod,st,med,i,p);
    else
        update(2*nod+1,med+1,dr,i,p);
    aint[nod]=max(aint[2*nod],aint[2*nod+1]);
}
void query(int nod,int st,int dr,int x,int y)
{
    if(x<=st && dr<=y)
        {
            ans=max(ans,aint[nod]);
            return;
        }
    int med=(st+dr)/2;
    if(med>=x)
        query(2*nod,st,med,x,y);
    if(med+1<=y)
        query(2*nod+1,med+1,dr,x,y);
}
int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int n,m,tip,x,y,a;
    scanf("%d%d",&n,&m);
    for(register int i=1;i<=n;i++)
        scanf("%d",&a),
        update(1,1,n,i,a);
    for(register int i=1;i<=m;i++)
    {
        scanf("%d%d%d",&tip,&x,&y);
        if(tip==0)
            ans=0,
            query(1,1,n,x,y),
            printf("%d\n",ans);
        else
            update(1,1,n,x,y);
    }
    return 0;
}