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#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int N, M;
vector<int>v, aib;
void update(int p, int v) {
for(int i = p; i <= N; i += lsb(i)) {
aib[i] += v;
}
}
int query(int p) {
int ret = 0;
for(int i = p; i >= 1; i -= lsb(i)) {
ret += aib[i];
}
return ret;
}
int main() {
fin >> N >> M;
v = vector<int>(N + 4);
aib = vector<int>(N + 4);
for(int i = 1; i <= N; i++) {
fin >> v[i];
update(i, v[i]);
}
for(int i = 1, q, a, b; i <= M; i++) {
fin >> q;
if(q == 0) {
fin >> a >> b;
update(a, b);
} else if(q == 1) {
fin >> a >> b;
fout << query(b) - query(a - 1) << '\n';
} else if(q == 2) {
fin >> a;
long long sum = 0, pos = 0, step, ans = -1;
int LGN = __lg(N);
for(int i = LGN; i >= 0; i--) {
if(pos + (1 << i) <= N) {
if(sum + aib[pos + (1 << i)] < a) {
sum += aib[pos + (1 << i)];
pos += (1 << i);
} else if(sum + aib[pos + (1 << i)] == a) {
ans = pos + (1 << i);
break;
}
}
}
fout << ans << '\n';
}
}
return 0;
}