#include<algorithm>
#include<bitset>
#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<deque>
#include<fstream>
#include<iomanip>
#include<iostream>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<vector>

using namespace std;

#ifdef HOME
const string inputFile = "input.txt";
const string outputFile = "output.txt";
#else
const string problemName = "aib";
const string inputFile = problemName + ".in";
const string outputFile = problemName + ".out";
#endif

const int NMAX = 100000 + 5;
const int INF = (1LL << 31) - 1;

int N, M;
int AIB[NMAX];

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

int query(int poz) {
    int ans = 0;
    for(; poz; poz -= poz & (-poz))
        ans += AIB[poz];
    return ans;
}

int bs(int sum) {
    int lo, hi, mi, p, ans = INF;

    lo = 1;
    hi = N;

    while(lo <= hi) {
        mi = (lo + hi) / 2;
        p = query(mi);

        if(p < sum)
            lo = mi + 1;
        else
            hi = mi - 1;

        if(p == sum)
            ans = min(ans, mi);
    }

    if(ans == INF)
        ans = -1;

    return ans;
}

int main() {
    int i, x, y, t;

#ifndef ONLINE_JUDGE
    freopen(inputFile.c_str(), "r", stdin);
    freopen(outputFile.c_str(), "w", stdout);
#endif

    scanf("%d%d", &N, &M);

    for(i = 1; i <= N; i++) {
        scanf("%d", &x);
        update(i, x);
    }

    while(M--) {
        scanf("%d", &t);

        if(t == 0) {
            scanf("%d%d", &x, &y);
            update(x, y);
            continue;
        }

        if(t == 1) {
            scanf("%d%d", &x, &y);
            printf("%d\n", query(y) - query(x - 1));
            continue;
        }

        if(t == 2) {
            scanf("%d", &x);
            printf("%d\n", bs(x));
            continue;
        }
    }

    return 0;
}