#include <bits/stdc++.h>
using namespace std;
 
#define NMAX 100005
 
class AIB {
    int zero(int x) { return (x ^ (x - 1)) & x; }
 
    int aib[NMAX], n;
 
    public:
        AIB(int size);
        int getSize();
        int getItem(int position);
        void update(int position, int value);
        int query(int position);
};
 
AIB::AIB(int size) {
    n = size;
    fill(aib, aib + n + 1, 0);
}
 
int AIB::getSize() {
    return n;
}
 
int AIB::getItem(int position) {
    return aib[position];
}
 
void AIB::update(int position, int value) {
    for(int i = position; i <= n; i += zero(i))
        aib[i] += value;
}
 
int AIB::query(int position) {
    int result = 0;
    for(int i = position; i > 0; i -= zero(i))
        result += aib[i];
    return result;
}
 
int binSearch(AIB& aib, int sum) {
    int left = 1, right = aib.getSize();
 
    while(left <= right) {
        int middle = (left + right) >> 1;
        int queryResult = aib.query(middle);
 
        if(queryResult == sum) {
            return middle;
        }
 
        if(queryResult > sum) 
            right = middle - 1;
        else left = middle + 1;
    }
 
    return -1;
}
 
int N, Q;
 
int main() {
    freopen("aib.in", "r", stdin);
    freopen("aib.out", "w", stdout);
 
    scanf("%d %d ", &N, &Q);    
 
    AIB arbore(N);
 
    for(int i = 1; i <= N; i++) {
        int item;
        scanf("%d ", &item);
        arbore.update(i, item);
    }
 
    for(int q = 1; q <= Q; q++) {
        int operation;
        scanf("%d ", &operation);
 
        if(operation == 0) {
            int position, value;
            scanf("%d %d ", &position, &value);
            arbore.update(position, value);
        }
        else if(operation == 1) {
            int left, right;
            scanf("%d %d ", &left, &right);
            int result = arbore.query(right) - arbore.query(left - 1);
            printf("%d\n", result);
        }
        else if(operation == 2) {
            int sum;
            scanf("%d ", &sum);
            int position = binSearch(arbore, sum);
            printf("%d\n", position);
        }
    }
 
    return 0;
}