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#include <bits/stdc++.h>
using namespace std;
int n, test, aib[100005];
void update(int idx, int x)
{
while(idx <= n){
aib[idx] += x;
idx += (idx&-idx);
}
}
int query(int x)
{
int sol = 0;
while(x){
sol += aib[x];
x -= (x&-x);
}
return sol;
}
int main()
{
ifstream fin ("aib.in");
ofstream fout ("aib.out");
fin >> n >> test;
for (int i = 1; i <= n; ++i){
int x;
fin >> x;
update(i, x);
}
while(test--){
int t;
fin >> t;
int a, b;
switch(t){
case 0:
fin >> a >> b;
update(a, b);
break;
case 1:
fin >> a >> b;
fout << query(b)-query(a-1) << "\n";
break;
case 2:
fin >> a;
int lo = 1, hi = n, m, ans = 2000000000;
for (m = (lo+hi)/2; lo <= hi; m = (lo+hi)/2){
b = query(m);
if(b == a)
ans = m;
if(b >= a)
hi = m-1;
else lo = m+1;
}
fout << (ans == 2000000000 ? -1 : ans) << "\n";
break;
}
}
return 0;
}