-
Notifications
You must be signed in to change notification settings - Fork 4
/
2166.cpp
73 lines (67 loc) · 1.63 KB
/
2166.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 2e5 + 5;
int n, q, x[N];
ll sum[N], ST[N << 2], lazy[N << 2];
void build(int id, int l, int r) {
if (l == r) {
ST[id] = sum[l];
return;
}
int mid = (l + r) >> 1;
build(id << 1, l, mid);
build(id << 1 | 1, mid + 1, r);
ST[id] = max(ST[id << 1], ST[id << 1 | 1]);
}
void down(int id) {
if (lazy[id] == 0) return;
ST[id << 1] += lazy[id];
ST[id << 1 | 1] += lazy[id];
lazy[id << 1] += lazy[id];
lazy[id << 1 | 1] += lazy[id];
lazy[id] = 0;
}
void update(int id, int l, int r, int u, int v, ll val) {
if (v < l || r < u) return;
if (u <= l && r <= v) {
ST[id] += val;
lazy[id] += val;
return;
}
down(id);
int mid = (l + r) >> 1;
update(id << 1, l, mid, u, v, val);
update(id << 1 | 1, mid + 1, r, u, v, val);
ST[id] = max(ST[id << 1], ST[id << 1 | 1]);
}
ll get(int id, int l, int r, int u, int v) {
if (v < l || r < u) return LLONG_MIN;
if (u <= l && r <= v) return ST[id];
down(id);
int mid = (l + r) >> 1;
return max(get(id << 1, l, mid, u, v), get(id << 1 | 1, mid + 1, r, u, v));
}
int main() {
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> n >> q;
for (int i = 1; i <= n; ++i) {
cin >> x[i];
}
for (int i = 1; i <= n; ++i) {
sum[i] = sum[i - 1] + x[i];
}
build(1, 1, n);
while (q--) {
int t, a, b; cin >> t >> a >> b;
if (t == 1) {
update(1, 1, n, a, n, b - x[a]);
x[a] = b;
} else {
ll pre = (a == 1) ? 0 : get(1, 1, n, a - 1, a - 1);
ll mx = max(get(1, 1, n, a, b), pre) - pre;
cout << mx << "\n";
}
}
return 0;
}