/*#include <bits/stdc++.h>
#define dim 100001 

using namespace std ;

ifstream fin("aib.in") ;
ofstream fout("aib.out") ;  
 
long long g[dim] , tree[4 * dim] , n ; 
 
int q ;  
int op ;
void build(int v , int tl , int tr){
	  
	  if(tl == tr) tree[v] = g[tl] ;  
	  else{
	  	  
	  	  int tm = (tl + tr) / 2 ; 
	  	  build(2 * v , tl , tm) ; 
	  	  build(2 * v + 1 , tm + 1 , tr) ; 
	  	  
	  	  tree[v] = tree[2 * v] + tree[2 * v + 1] ;  
	  	  
	  }
}
void update(int v , int tl , int tr , int poz , int val){
	  
	  if(tl == tr) tree[v] += val ; 
	  else{
	  	 
	  	 int tm = (tl + tr) / 2 ; 
	  	 if(poz <= tm) update(2 * v , tl ,tm , poz , val) ; 
	  	 else update(2 * v + 1 , tm + 1 , tr , poz , val) ; 
	  	 
	  	 tree[v] = tree[2 * v] + tree[2 * v + 1] ;  
	  }
} 
long long query(int v , int tl , int tr , int st , int dr){
	  
	  if(tl > dr || tr < st) return 0 ; 
	  
	  if(tl >= st && tr <= dr) return tree[v] ; 
	  
	  int tm = (tl + tr) / 2 ;  
	  
	  return query(2 * v , tl , tm , st , dr) + query(2 * v + 1 , tm + 1 , tr , st , dr) ; 
} 

long long binary(int v , int tl , int tr , long long a){
	  
	if(tl == tr){
		 
		 if(tree[v] == a) return tl ;
		 
		 return -1 ;   
	}
	
	int tm = (tl + tr) / 2 ;
	
	if(tree[2 * v] >= a) return binary(2 * v , tl , tm , a) ; 
	else return binary(2 * v + 1 , tm + 1 , tr , a - tree[2 * v]) ;  
	
} 

int main()
{
   ios::sync_with_stdio(false);
   cin.tie(0) ;
   
   fin >> n >> q ;  
   for(int i = 1 ; i <= n ; ++i) fin >> g[i] ; 
   
   build(1 , 1 , n) ;  
   
   while(q--){
   	   
   	   fin >> op ; 
	   if(op == 0){
	   	   
	   	   int poz , val ; 
	   	   fin >> poz >> val ; 
	   	   
	   	   update(1 , 1 , n , poz , val) ; 
	   }  
	   else if(op == 1){
	   	   
	   	   int a , b ;
	   	   fin >> a >> b ;
	   	   
	   	   fout << query(1 , 1 , n , a , b) << '\n' ;  
	   }
	   else{
	   	 
	   	 ///op = 2 : 
	   	  
	   	 long long a ;
	   	 fin >> a ;  
	   	 if(tree[1] < a) fout << -1 << '\n' ; 
	   	 else fout << binary(1 , 1 , n , a) << '\n' ;  
	   } 
	   
   }
   return 0 ;
}
*/
#include <bits/stdc++.h>
using namespace std;
const int MAXN = 100000 + 5;
long long g[MAXN], tree[4 * MAXN];
int n, m;

void build(int v, int tl, int tr){
    if(tl == tr) tree[v] = g[tl];
    else{
        int tm = (tl + tr) >> 1;
        build(v<<1, tl, tm);
        build(v<<1|1, tm+1, tr);
        tree[v] = tree[v<<1] + tree[v<<1|1];
    }
}

void update(int v, int tl, int tr, int pos, int val){
    if(tl == tr) tree[v] += val;
    else{
        int tm = (tl + tr) >> 1;
        if(pos <= tm) update(v<<1, tl, tm, pos, val);
        else update(v<<1|1, tm+1, tr, pos, val);
        tree[v] = tree[v<<1] + tree[v<<1|1];
    }
}

long long query(int v, int tl, int tr, int l, int r){
    if(l > r || tl > r || tr < l) return 0;
    if(tl >= l && tr <= r) return tree[v];
    int tm = (tl + tr) >> 1;
    return query(v<<1, tl, tm, l, r) + query(v<<1|1, tm+1, tr, l, r);
}

int find_prefix_exact(int v, int tl, int tr, long long a){
    if(a == 0) return 0;
    if(tl == tr){
        if(tree[v] == a) return tl;
        return -1;
    }
    int tm = (tl + tr) >> 1;
    if(tree[v<<1] >= a) return find_prefix_exact(v<<1, tl, tm, a);
    else return find_prefix_exact(v<<1|1, tm+1, tr, a - tree[v<<1]);
}

int main(){
    if(scanf("%d %d", &n, &m)!=2) return 0;
    for(int i = 1; i <= n; ++i) scanf("%lld", &g[i]);
    build(1, 1, n);
    while(m--){
        int op;
        scanf("%d", &op);
        if(op == 0){
            int a, b; scanf("%d %d", &a, &b);
            update(1, 1, n, a, b);
        } else if(op == 1){
            int a, b; scanf("%d %d", &a, &b);
            printf("%lld\n", query(1, 1, n, a, b));
        } else if(op == 2){
            long long a; scanf("%lld", &a);
            if(a == 0){ printf("0\n"); continue; }
            if(tree[1] < a){ printf("-1\n"); continue; }
            int res = find_prefix_exact(1, 1, n, a);
            printf("%d\n", res);
        }
    }
    return 0;
}