推导见pecco树状数组

板子

int n;
const int M = 2e5 + 9;
int tree[M];

int lowbit(int x) {
    return x & (-x);
}

void update(int x, int y) {//建树
    for (int pos = x;pos <= n;pos += lowbit(pos))
        tree[pos] += y;
}

int ask(int x) {//查询单点值
    int ans = 0;
    for (int pos = x;pos;pos -= lowbit(pos))
        ans += tree[pos];
    return ans;
}

int query(int x,int y) {//查询区间和
    return ask(y) - ask(x - 1);
}

板子题1

洛谷树状数组板子1

/*

//单点修改
void change(int i, int x) {
    for (int pos = i;pos <= M;pos += lowbit(pos))
        tree[pos] += x;
}
//区间查询
void query(int x, int y) {
    return ask(y) - ask(x - 1);
}
void ask(int x) {
    int ans = 0;
    for (int pos = x;po;pos -= lowbit(pos))
        ans += tree(pos);
    return ans;
}
*/

#include<bits/stdc++.h>

using namespace std;

const int M = 5e5 + 9;
int tree[M];

#define int long long

int lowbit(int x) {
    return x & (-x);
}

void add(int x, int y) {
    for (int pos = x;pos < M;pos += lowbit(pos))
        tree[pos] += y;
}

int ask(int x) {
    int ans = 0;
    for (int pos = x;pos;pos -= lowbit(pos))
        ans += tree[pos];
    return ans;
}


int query(int x, int y) {
    return ask(y) - ask(x - 1);
}

signed main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int n, m;cin >> n >> m;
    for (int i = 1;i <= n;i++) {
        int p;cin >> p;
        add(i, p);
    }
    while (m--) {
        int a;cin >> a;
        int b, c;cin >> b >> c;
        if (a == 1)add(b, c);
        if (a == 2)cout << query(b, c) << '\n';
    }
    return 0;
}