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#include <bits/stdc++.h>
using namespace std;
namespace BIT {
vector<int> bit;
int n;
int lsb(int x) {
return x & -x;
}
void init(int _n) {
n = _n;
bit.resize(n + 1);
for (int i = 0; i <= n; i++)
bit[i] = 0;
}
void update(int pos, int val) {
if (pos == 0)
return;
for (int i = pos; i <= n; i += lsb(i))
bit[i] += val;
}
int query(int pos) {
int ans = 0;
for (int i = pos; i > 0; i -= lsb(i))
ans += bit[i];
return ans;
}
int query(int left, int right) {
return query(right) - query(left - 1);
}
int binarySearch(int sum) {
int ans = 0, s = 0;
for (int jump = (1 << 17); jump > 0; jump >>= 1)
if (ans + jump <= n && s + bit[ans + jump] <= sum) {
ans += jump;
s += bit[ans];
}
return ans;
}
}
signed main() {
ifstream fin("aib.in");
ofstream fout("aib.out");
int n, q;
fin >> n >> q;
BIT::init(n);
for (int i = 1; i <= n; i++) {
int x;
fin >> x;
BIT::update(i, x);
}
while (q--) {
int type;
fin >> type;
if (type == 0) {
int pos, val;
fin >> pos >> val;
BIT::update(pos, val);
} else if (type == 1) {
int left, right;
fin >> left >> right;
fout << BIT::query(left, right) << '\n';
} else {
int sum;
fin >> sum;
fout << BIT::binarySearch(sum) << '\n';
}
}
fin.close();
fout.close();
return 0;
}