Cod sursa(job #1690588)

Utilizator isa_mirica_mihaiMirica Matei isa_mirica_mihai Data 15 aprilie 2016 12:16:26
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.29 kb
#include <cstdio>
using namespace std;
int tree[400005], max1;
int MAX(int a, int b){
    if (a > b)
        return a;
    return b;
}
void update(int nod, int st, int dr, int poz, int val){
    if (st == dr){
        tree[nod] = val;
        return ;
    }
    int mid = (st + dr) / 2;
    if (mid < poz)
        update(2 * nod + 1, mid + 1, dr, poz, val);
    else
        update(2 * nod, st, mid, poz, val);
    tree[nod] = MAX(tree[2 * nod], tree[2 * nod + 1]);
}
void query(int nod, int st, int dr, int a, int b){
    if(a <= st && dr <= b){
        max1 = MAX(max1, tree[nod]);
        return ;
    }
    int mid = (st + dr) / 2;
    if (a <= mid)
        query(2 * nod, st, mid, a, b);
    if (b > mid)
        query(2 * nod + 1, mid + 1, dr, a, b);
}
int main(){
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    int n, m, i, op, a, b;
    scanf("%d%d", &n, &m);
    for (i = 1; i <= n; i ++){
        scanf("%d", &a);
        update(1, 1, n, i, a);
    }
    for (i = 1; i <= m; i ++){
        scanf("%d%d%d", &op, &a, &b);
        if (op == 0){
            max1 = 0;
            query(1, 1, n, a, b);
            printf("%d\n", max1);
        }
        else{
            update(1, 1, n, a, b);
        }
    }
    return 0;
}