#include <iostream>
#include <complex>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <numeric>
#include <cstring>
#include <ctime>
#include <cstdlib>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <cmath>
#include <bitset>
#include <cassert>
#include <queue>
#include <stack>
#include <deque>
#include <random>
#include <iomanip>
using namespace std;
template<typename T1, typename T2> inline void chkmin(T1 &a, T2 b) {if (a > b) a = b;}
template<typename T1, typename T2> inline void chkmax(T1 &a, T2 b) {if (a < b) a = b;}
#define files(FILENAME) read(FILENAME); write(FILENAME)
#define read(FILENAME) freopen((FILENAME + ".in").c_str(), "r", stdin)
#define write(FILENAME) freopen((FILENAME + ".out").c_str(), "w", stdout)
#define all(c) (c).begin(), (c).end()
#define sz(c) (int)(c).size()
#define left left228
#define right right228
#define y1 y1228
#define mp make_pair
#define pb push_back
#define y2 y2228
#define rank rank228
using ll = long long;
using ld = long double;
const string FILENAME = "input";
const int MAXN = 500 + 7;
int n, k;
pair<int, int> a[MAXN];
ld dp[MAXN][MAXN];
ld f(int kek) {
for (int i = 0; i <= n; i++) {
for (int j = 0; j <= n; j++) {
dp[i][j] = 1e9;
}
}
dp[0][0] = 0;
for (int i = 1; i <= n; i++) {
for (int j = 0; j <= i; j++) {
int c = i - j;
if (c <= kek && i - j != 0) {
chkmin(dp[i][j], dp[i - 1][j] + (ld) a[i].first / (ld) c);
} else if (c > kek) {
chkmin(dp[i][j], dp[i - 1][j]);
}
if (j >= 1) {
chkmin(dp[i][j], dp[i - 1][j - 1] + (ld) a[i].second / (ld) (kek + 1));
}
}
}
return dp[n][k - kek];
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
//read(FILENAME);
cout << setprecision(10) << fixed;
cin >> n >> k;
for (int i = 1; i <= n; i++) {
cin >> a[i].second >> a[i].first;
}
for (int i = 1; i <= n; i++) {
if (a[i].first == -1) {
a[i].first = 1e9;
}
}
sort(a + 1, a + n + 1);
int l = 1, r = n, sol = 0;
while (l <= r) {
int m = (l + r) >> 1;
if (f(m) < f(m - 1)) {
l = m + 1;
sol = m;
} else {
r = m - 1;
}
}
ld res = min(f(sol), f(0));
res = (ld) ((ld) res * (ld) 1e10) / (ld) 1e10;
cout << res << '\n';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
344 KB |
Output is correct |
3 |
Correct |
0 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Correct |
33 ms |
4184 KB |
Output is correct |
6 |
Correct |
32 ms |
4440 KB |
Output is correct |
7 |
Correct |
33 ms |
4188 KB |
Output is correct |
8 |
Correct |
33 ms |
4412 KB |
Output is correct |
9 |
Correct |
34 ms |
4184 KB |
Output is correct |
10 |
Correct |
33 ms |
4184 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
344 KB |
Output is correct |
3 |
Correct |
0 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Correct |
33 ms |
4184 KB |
Output is correct |
6 |
Correct |
32 ms |
4440 KB |
Output is correct |
7 |
Correct |
33 ms |
4188 KB |
Output is correct |
8 |
Correct |
33 ms |
4412 KB |
Output is correct |
9 |
Correct |
34 ms |
4184 KB |
Output is correct |
10 |
Correct |
33 ms |
4184 KB |
Output is correct |
11 |
Correct |
0 ms |
344 KB |
Output is correct |
12 |
Incorrect |
45 ms |
4432 KB |
Output isn't correct |
13 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
44 ms |
4184 KB |
Output is correct |
2 |
Correct |
42 ms |
4184 KB |
Output is correct |
3 |
Correct |
43 ms |
4184 KB |
Output is correct |
4 |
Correct |
44 ms |
4420 KB |
Output is correct |
5 |
Correct |
43 ms |
4184 KB |
Output is correct |
6 |
Correct |
44 ms |
4416 KB |
Output is correct |
7 |
Correct |
43 ms |
4184 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
344 KB |
Output is correct |
3 |
Correct |
0 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Correct |
33 ms |
4184 KB |
Output is correct |
6 |
Correct |
32 ms |
4440 KB |
Output is correct |
7 |
Correct |
33 ms |
4188 KB |
Output is correct |
8 |
Correct |
33 ms |
4412 KB |
Output is correct |
9 |
Correct |
34 ms |
4184 KB |
Output is correct |
10 |
Correct |
33 ms |
4184 KB |
Output is correct |
11 |
Correct |
0 ms |
344 KB |
Output is correct |
12 |
Incorrect |
45 ms |
4432 KB |
Output isn't correct |
13 |
Halted |
0 ms |
0 KB |
- |