0
1
mirror of https://git.sb/baoshuo/OI-codes.git synced 2024-12-25 18:12:04 +00:00
OI-codes/Luogu/P3353/P3353.cpp

69 lines
1.3 KiB
C++

#include <bits/stdc++.h>
using namespace std;
struct node {
int l, r, s;
node() {
l = r = s = 0;
}
node(int _l, int _r) {
l = _l;
r = _r;
s = 0;
}
} tr[1000005 << 2];
int n, w, x, b, ans;
void pushup(int u) {
tr[u].s = tr[u << 1].s + tr[u << 1 | 1].s;
}
void build(int u, int l, int r) {
tr[u] = node(l, r);
if (l == r) return;
int mid = l + r >> 1;
build(u << 1, l, mid);
build(u << 1 | 1, mid + 1, r);
}
void modify(int u, int p, int d) {
if (tr[u].l == p == tr[u].r) {
tr[u].s += d;
return;
}
int mid = tr[u].l + tr[u].r >> 1;
if (p <= mid) {
modify(u << 1, p, d);
} else {
modify(u << 1 | 1, p, d);
}
pushup(u);
}
int query(int u, int l, int r) {
if (l <= tr[u].l && tr[u].r <= r) {
return tr[u].s;
}
int mid = tr[u].l + tr[u].r >> 1;
int s = 0;
if (l <= mid) s += query(u << 1, l, r);
if (r > mid) s += query(u << 1 | 1, l, r);
return s;
}
int main() {
cin >> n >> w;
build(1, 1, 100000);
for (int i = 0; i < n; i++) {
cin >> x >> b;
modify(1, x, b);
}
for (int i = 1; i + w <= 100000; i++) {
ans = max(ans, query(1, i, i + w - 1));
}
cout << ans << endl;
return 0;
}