Cod sursa(job #3365769)

Utilizator TimofeiFilipTimofei Filip Emanuel TimofeiFilip Data 24 septembrie 2026 09:07:26
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.81 kb
#include<bits/stdc++.h>
using namespace std;

const int NMAX = 1e5 + 10;
typedef long long int ll;

ll tree[NMAX], v[NMAX];
int n, queries;

void compute_input() {
    scanf("%d %d", &n, &queries);
    for (int i = 1; i <= n; i++) scanf("%lld", &v[i]);
}

void add(int index, ll value) {
    while (index <= n) {
        tree[index] += value;
        index = index + (index & -index);
    }
}
void build_tree() {
    for (int i = 1; i <= n; i++) {
        tree[i] += v[i];
        int j = i + (i & -i);
        if (j <= n)
            tree[j] += tree[i];
    }
}
ll get_prefix(int index) {
    if (index <= 0) return 0;
    ll sum = 0;
    while (index >= 1) {
        sum += tree[index];
        index = index - (index & -index);
    }
    return sum;
}

ll query(int left, int right) {
    return get_prefix(right) - get_prefix(left - 1);
}
void update(int position, int new_value) {
    add(position, new_value);
}
int order_sum(ll target) {
    int left, right;
    left = 1; right = n;
    int result = 0;
    while (left <= right) {
        int middle = (left + right) / 2;
        if (get_prefix(middle) >= target) {
            result = middle;
            right = middle - 1;
        }
        else
            left = middle + 1;
    }
    return ((get_prefix(result) == target) ? result : -1);
}
void compute_output() {
    for (; queries > 0; queries--) {
        int op, x, y;
        scanf("%d %d", &op, &x);
        if (op == 1) {
            scanf("%d", &y);
            printf("%lld\n", query(x, y));
        }
        else if (op == 0) {
            scanf("%d", &y);
            update(x, y);
        }
        else {
            printf("%d\n", order_sum(x));
        }
    }
}

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

    compute_input();
    build_tree();
    compute_output();
    return 0;
}