#include <cstdio>
#include <vector>

#define DIM 66013
#define nextp p&(p^(p-1))

using namespace std;

char buffer[DIM];
int poz = DIM - 1;

void Scanf(int &A){
    A = 0;
    while('0' > buffer[poz] || buffer[poz] > '9')
        if(++poz == DIM)
            fread(buffer,1,DIM,stdin),poz = 0;
    while('0' <= buffer[poz] && buffer[poz] <= '9')
    {
        A = A * 10 + buffer[poz] - 48;
        if(++poz == DIM)
            fread(buffer,1,DIM,stdin),poz = 0;
    }
}
int N,M;

class FenwickTree{
public:
    vector<int> range;
    int answer;
    void Resize(int N){
        range.resize(N+1);
    }
    void Update(int pz,int val){
        for(int p = pz; p <= N; p += nextp)
            range[p] += val;
    }
    int Querry(int pz){
        answer = 0;
        for(int p = pz; p; p -= nextp)
            answer = answer + range[p];
        return answer;
    }
};
FenwickTree AIB;


void Read()
{
    Scanf(N);Scanf(M);
    AIB.Resize(N+1);
    int v;
    for(int i = 1; i <= N; ++i){
        Scanf(v);
        AIB.Update(i,v);
    }

}

void Solve()
{
    int t,a,b;
    for(int i = 1; i <= M; ++i)
    {
        Scanf(t);
        if(t == 0){
            Scanf(a);Scanf(b);
            AIB.Update(a,b);
            continue;
        }
        if(t == 1){
            Scanf(a);Scanf(b);
            printf("%d\n",AIB.Querry(b) - AIB.Querry(a-1));
            continue;
        }
        Scanf(a);
        int li = 1,lf = N,m;
        while(li <= lf){
            m = li +((lf-li) >> 1);
            if(AIB.Querry(m) >= a)
                lf = m - 1;
            else
                li = m + 1;
        }
        if(AIB.Querry(li) == a)
            printf("%d\n",li);
        else
            printf("-1\n");
    }
}

int main()
{
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);

    Read();
    Solve();

    return 0;
}