#include <iostream>
#include <cstdio>
using namespace std;
const int NMAX = 100002;
int aib[NMAX],aibSize;
void add(int poz, int val){
    do{
        aib[poz] += val;
        poz += poz & (-poz);
    }while(poz <= aibSize);
}
int sum(int poz){
    int result = 0;
    while(poz){
        result += aib[poz];
        poz -= poz & (-poz);
    }
    return result;
}
int search(int low, int high, int val){
    int middle, x;
    while(low <= high){
        middle = (low + high) / 2;
        x = sum(middle);
        if(x == val)
            return middle;
        else if(x > val)
            high = middle - 1;
        else
            low = middle + 1;
    }
    return -1;
}
int main()
{
    FILE *fin, *fout;
    int n,m,i,op,a,b,ans;
    fin = fopen("aib.in","r");
    fout = fopen("aib.out","w");
    fscanf(fin,"%d %d",&n,&m);
    aibSize = n;
    for(i=1;i<=n;i++){
        fscanf(fin,"%d",&a);
        add(i,a);
    }
    for(i=1;i<=m;i++){
        fscanf(fin,"%d %d",&op,&a);
        if(op != 2)
            fscanf(fin,"%d",&b);
        if(op == 0)
            add(a,b);
        else{
            if(op == 1)
                ans = sum(b) - sum(a - 1);
            else
                ans = search(1,n,a);
            fprintf(fout,"%d\n",ans);
        }
    }
    fclose(fin);
    fclose(fout);
    return 0;
}