#include <bits/stdc++.h>

using namespace std;

using ll = long long;
const int INF=1e9+7;
const ll INFF=1e18+7;
#define nl '\n'
void __print(int x) { cout << x; }
void __print(long x) { cout << x; }
void __print(long long x) { cout << x; }
void __print(unsigned x) { cout << x; }
void __print(unsigned long x) { cout << x; }
void __print(unsigned long long x) { cout << x; }
void __print(float x) { cout << x; }
void __print(double x) { cout << x; }
void __print(long double x) { cout << x; }
void __print(char x) { cout << '\'' << x << '\''; }
void __print(const char* x) { cout << '\"' << x << '\"'; }
void __print(const string& x) { cout << '\"' << x << '\"'; }
void __print(bool x) { cout << (x ? "true" : "false"); }
template<typename T, typename V>
void __print(const pair<T, V>& x) { cout << '{'; __print(x.first); cout << ','; __print(x.second); cout << '}'; }
template<typename T>
void __print(const T& x) { int f = 0; cout << '{'; for (auto& i : x) cout << (f++ ? "," : ""), __print(i); cout << "}"; }
void _print() { cout << "]\n"; }
template <typename T, typename... V>
void _print(T t, V... v) { __print(t); if (sizeof...(v)) cout << ", "; _print(v...); }
#ifndef ONLINE_JUDGE
#define debug(x...) cout << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

int n,q;
vector<int> a;

void update(int pos, int val){
    for(int i=pos; i<=n; i+=i&-i){
        a[i]+=val;
    }
}

ll sum(int pos){
    ll s=0;
    for(int i=pos; i>0; i-=i&-i){
        s+=a[i];
    }
    return s;
}

void solve()
{
    cin>>n>>q;
    a.resize(n+1);
    for(int i=1; i<=n; i++){
        int x; cin>>x;
        update(i,x);
    }
    for(int i=0; i<q; i++){
        int c; cin>>c;
        if(c==0){
            int x,y;
            cin>>x>>y;
            update(x,y);
        }
        else if(c==1){
            int x,y;
            cin>>x>>y;
            cout<<sum(y)-sum(x-1)<<nl;
        }
        else{
            ll x; cin>>x;
            bool ok=false;
            int st=0, dr=n;
            while(st<=dr && !ok){
                int mid=(st+dr)/2;
                ll s=sum(mid);
                if(s==x){
                    cout<<mid<<nl;
                    ok=true;
                }
                else if(s>x){
                    dr=mid-1;
                }
                else st=mid+1;
            }
            if(!ok){
                cout<<"-1\n";
            }
        }
    }
}

int main()
{
    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);

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

    ios::sync_with_stdio(0);
    cin.tie(0);
    int t=1;
    // int t;
    // cin >> t;
    for(int tt=1; tt<=t; tt++){
        // cout<<"#Case "<<t<<nl;
        solve();
    }
    return 0;
}