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#include <algorithm>
#include <iostream>
#include <vector>
class SumFenwickTree {
public:
SumFenwickTree(int n) : a(n+1) {}
long long sum(int l, int r) const { return psum(r) - psum(l-1); }
void update(int k, long long u) { add(k, u - sum(k, k));}
private:
std::vector<long long> a;
static int lsb(int i) { return i & -i; }
long long psum(int i) const {
long long s = 0;
while (i > 0) {
s += a[i];
i -= lsb(i);
}
return s;
}
void add(int k, long long d) {
while (k < (int)a.size()) {
a[k] += d;
k += lsb(k);
}
}
};
int main() {
size_t n, q;
std::cin >> n >> q;
SumFenwickTree t(n);
for (size_t i = 0; i < n; i++) {
long long x;
std::cin >> x;
t.update(i+1, x);
}
for (size_t i = 0; i < q; i++) {
long long x, k, u;
std::cin >> x >> k >> u;
if (x == 1)
t.update(k, u);
else
std::cout << t.sum(k, u) << "\n";
}
}
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