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c_cpp
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#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <ctime>
#include <cassert>
#include <complex>
#include <string>
#include <cstring>
#include <chrono>
#include <random>
#include <bitset>
#include <array>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using db = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<db, db>;
using tiii = tuple<int, int, int>;
using str = string;
#define vt vector
#define pb push_back
#define eb emplace_back
#define ins insert
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second
struct segtree {
vector<ll> tree;
int size;
void init(int n) {
size = 1;
while (size < n) size *= 2;
tree.assign(2 * size - 1, 0);
}
void build(vt<int> &a, int x, int lx, int rx) {
if (rx - lx == 1) {
if (lx < a.size())
tree[x] = a[lx];
} else {
int m = (rx + lx) / 2;
build(a, 2 * x + 1, lx, m);
build(a, 2 * x + 2, m, rx);
tree[x] = tree[2 * x + 1] + tree[2 * x + 2];
}
}
void build(vt<int> &a) {
init((int)a.size());
build(a, 0, 0, size);
}
void set(int i, int v, int x, int lx, int rx) {
if (rx - lx == 1) {
tree[x] = v;
return;
}
int m = (lx + rx)/2;
if (i < m) {
set(i, v, 2 * x + 1, lx, m);
}
else {
set(i, v, 2 * x + 2, m, rx);
}
tree[x] = tree[2 * x + 1] + tree[2 * x + 2];
}
void set(int i, int v) {
set(i, v, 0, 0, size);
}
ll sum(int l, int r , int x, int lx, int rx) {
if (l >= rx || lx >= r) {
return 0;
}
if (lx >= l && rx <= r){
return tree[x];
}
int m = (lx + rx) / 2;
ll s1 = sum(l, r, 2 * x + 1, lx, m);
ll s2 = sum(l, r, 2 * x + 2, m, rx);
return s1 + s2;
}
ll sum(int l, int r){
return sum(l, r, 0, 0, size);
}
};
void solve() {
int n, m;
cin >> n >> m;
vt<int> a(n);
for (int i = 0; i < n; ++i) {
cin >> a[i];
}
segtree st;
st.build(a);
for (int t = 0; t < m; ++t) {
int c;
cin >> c;
if (c == 1) {
int i, v;
cin >> i >> v;
st.set(i, v);
}
else {
int l, r;
cin >> l >> r;
cout << st.sum(l, r) << '\n';
}
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
// freopen("data.in", "r", stdin);
// freopen("data.out", "w", stdout);
int t = 1;
// cin >> t;
while (t--) {
solve();
}
return 0;
}
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