p3374 【模板】树状数组 1

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
using namespace std;
int tree[2000010];
int m,n;
int lowbit(int k)
{
    return k & -k;
}
void add(int x,int k)
{
    while(x<=m)
    {
        tree[x] += k;
        x += lowbit(x);
    }
}
int sum(int x)
{
    int sum = 0;
    while(x!=0)
    {
        sum += tree[x];
        x -= lowbit(x);
    }
    return sum;
}
int main()
{
    cin >> m >> n;
    for (int i = 1; i <= m;i++)
    {
        int temp;
        cin >> temp;
        add(i, temp);
    }
    for (int i = 1; i <= n;i++)
    {
        int a, b, c;
        cin >> a >> b >> c;
        if(a==1)
        {
            add(b, c);
        }
        else
        {
            cout << sum(c) - sum(b-1) << endl;
        }  
    }
}