#include <stdio.h>
#include <iostream>
#define N_MAX 100005
#define N_LOG 20

using namespace std;

int n, m;
int aib[N_MAX];

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

// void build (){
//     for (int i=1; i<=n; ++i){
//         aib[i] += arr[i];

//         if (i + leastSignificantBit(i) <= n)
//             aib[i + leastSignificantBit(i)] += aib[i];
//     }
// }

void update (int idx, int value){
    // arr[idx] = value;
    while (idx <= n){
        aib[idx] += value;
        idx += leastSignificantBit(idx);
    }
}

int query (int Idx){
    long long Sum = 0;

    while (Idx){
        Sum += aib[Idx];
        Idx -= leastSignificantBit(Idx);
    }

    return Sum;
}

int binaryLifting (int value){
    int pos = 0, sum = 0;

    for (int mask = 24; mask>=0; mask--){
        if (pos + (1<<mask) <= n && sum + aib[pos+(1<<mask)] < value){
            sum += aib[pos+(1<<mask)];
            pos += (1<<mask);
        }
    }
    pos++;
    
    if (pos > n || query(pos) != value)
        return -1;
    return pos;
}

int main (){
    FILE *in, *out;
    in = fopen ("aib.in", "r");
    out = fopen ("aib.out", "w");

    fscanf(in, "%d%d", &n, &m);
    int num;
    for (int i=1; i<=n; ++i){
        fscanf (in, "%d", &num);
        update(i, num);
    }
    
    int op, x, y;
    for (int i=1; i<=m; ++i){
        fscanf(in, "%d", &op);
        if (op == 0){
            fscanf(in, "%d%d", &x, &y);
            update(x, y);
        }
        else if (op == 1){
            fscanf(in, "%d%d", &x, &y);
            fprintf (out, "%d \n", query(y) - query(x-1));
        }
        else{
            fscanf(in, "%d", &x);
            fprintf(out, "%d \n", binaryLifting(x));
        }
    }
    return 0;
}