Cod sursa(job #1690584)

Utilizator raddudjPogonariu Radu raddudj Data 15 aprilie 2016 12:07:55
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.1 kb
#include<cstdio>
#include<algorithm>

using namespace std;

int ans;
int aint[400005];

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