#include <cstdio>
using namespace std;
#define NMAX 100005

int n, m, aib[NMAX], a[NMAX];

void update(int poz, int val) {
    for(; poz<=n; poz += poz&-poz)
        aib[poz] += val;
}

int querry(int poz) {
    int s = 0;
    for(; poz>0; poz-=poz&-poz)
        s += aib[poz];
    
    return s;
}

int pozitie(int x) {
    int last = -1, med;
    int st = 1;
    int dr = n;
    
    while(st <= dr) {
        med = (st + dr)/2;
        if(querry(med) < x) 
          st = med + 1;
        else 
        if(querry(med) > x)
          dr = med - 1;
        else {
          last = med;
          break;
        }
    }
    
    return last;
}

int main()
{
    int i, test, x, y;
    FILE *fin, *fout;
    fin = fopen("aib.in", "r");
    fout = fopen("aib.out", "w");
    
    fscanf(fin, "%d %d", &n, &m);
    for(i=1; i<=n; i++) {
      fscanf(fin, "%d ", &a[i]);
    
      update(i, a[i]);
    }
    
    for(i=1; i<=m; i++) {
      fscanf(fin, "%d ", &test);
      if(test == 0) {
        fscanf(fin, "%d %d", &x, &y);
        update(x, y);
      }
      else
      if(test == 1) {
        fscanf(fin, "%d %d", &x, &y);
        fprintf(fout, "%d\n", querry(y) - querry(x-1));
      }
      else {
        fscanf(fin, "%d", &x);
        fprintf(fout, "%d\n", pozitie(x));
      }
    }
    
    fclose(fin);
    fclose(fout);
    return 0;
}