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#include <fstream>
#define NMAX 100010
std::ifstream fin("aib.in");
std::ofstream fout("aib.out");
int n, q;
int aib[NMAX];
inline int lsb(int x) {
return x & (-x);
}
void update(int pos, int val) {
for (int i = pos; i <= n; i += lsb(i))
aib[i] += val;
}
int query(int pos) {
int sum = 0;
for (int i = pos; i >= 1; i -= lsb(i))
sum += aib[i];
return sum;
}
int search(int val) {
int md, lo = 0, hi = n + 1;
while (hi - lo > 1) {
md = (lo + hi) >> 1;
if (query(md) < val)
lo = md;
else
hi = md;
}
return hi <= n ? hi : -1;
}
int main() {
fin >> n >> q;
for (int i = 1; i <= n; i++) {
int x; fin >> x;
update(i, x);
}
for (int it = 0; it < q; it++) {
int t, x, y;
fin >> t >> x;
if (t < 2)
fin >> y;
if (!t)
update(x, y);
else if (t == 1)
fout << query(y) - query(x - 1) << '\n';
else
fout << search(x) << '\n';
}
fout.close();
return 0;
}