-
Notifications
You must be signed in to change notification settings - Fork 0
/
F2.cpp
77 lines (66 loc) · 1.78 KB
/
F2.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
74
75
76
77
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> Pii;
typedef pair<int, ll> Pil;
typedef pair<ll, ll> Pll;
typedef pair<ll, int> Pli;
typedef vector<vector<ll>> Mat;
#define fi first
#define se second
const ll MOD = 1e9 + 7;
const ll MOD2 = 998244353;
const ll MOD3 = 1812447359;
const ll INF = 1ll << 62;
const double PI = 2 * asin(1);
void yes() { printf("yes\n"); }
void no() { printf("no\n"); }
void Yes() { printf("Yes\n"); }
void No() { printf("No\n"); }
void YES() { printf("YES\n"); }
void NO() { printf("NO\n"); }
int n, k;
ll sx, sy, x[int(2e5 + 5)], y[int(2e5 + 5)];
double ans = 0;
double dp[int(2e5 + 5)];
double dist(ll x0, ll y0, ll x1, ll y1) {
return sqrt((x0 - x1) * (x0 - x1) + (y0 - y1) * (y0 - y1));
}
priority_queue<pair<double, int>, vector<pair<double, int>>,
greater<pair<double, int>>>
que;
double search_min(int idx) {
while (que.top().second < idx - k) {
que.pop();
}
return que.top().first;
}
int main() {
cin >> n >> k;
cin >> sx >> sy;
for (int i = 1; i <= n; i++) {
cin >> x[i] >> y[i];
}
ans += dist(sx, sy, x[1], y[1]);
for (int i = 2; i <= n; i++) {
ans += dist(x[i - 1], y[i - 1], x[i], y[i]);
}
ans += dist(x[n], y[n], sx, sy);
que.push({0, 1});
for (int i = 2; i <= n; i++) {
double direct = dist(x[i - 1], y[i - 1], x[i], y[i]);
double via_home =
dist(x[i - 1], y[i - 1], sx, sy) + dist(sx, sy, x[i], y[i]);
double min_dist = search_min(i);
dp[i] = min_dist + via_home - direct;
que.push({dp[i], i});
}
double min_penalty = 1e18;
for (int i = max(1, n - k + 1); i <= n; i++) {
min_penalty = min(min_penalty, dp[i]);
}
ans += min_penalty;
cout << fixed << setprecision(32) << ans << endl;
return 0;
}