#include<cstdio>
#include<string>

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;

int N, M;
int A[NMAX];
int AIB[NMAX];

void update(int poz, int val) {
    int i;

    for(i = poz; i <= N; i += i & (-i))
        AIB[i] += val;
}

int query(int poz) {
    int i, ans = 0;

    for(i = poz; i; i -= i & (-i))
        ans += AIB[i];

    return ans;
}

int bs(int sum) {
    int lo = 1, hi = N, mi, sol = -1, s;

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

        if(s == sum)
            sol = mi;

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

    return sol;
}

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

    freopen(inputFile.c_str(), "r", stdin);
    freopen(outputFile.c_str(), "w", stdout);

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

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

    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;
}