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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#227335 | #6801. Blackjack | jzh | WA | 1ms | 3712kb | C++23 | 1.1kb | 2023-10-27 12:30:18 | 2023-10-27 12:30:18 |
Judging History
answer
#include <algorithm>
#include<bits/stdc++.h>
using namespace std;
using db = double;
const int maxn = 510;
void solve() {
int n, a, b; cin >> n >> a >> b;
vector<int>vec(n);
for(int i = 0 ; i < n ; i ++) cin >> vec[i];
vector<vector<db>>dp(n+1, vector<db>(b+1));
auto ndp = dp;
dp[0][0] = 1;
for(int i = 0 ; i < n ; i ++) {
for(auto &v: ndp) fill(begin(v), end(v), 0);
for(int x = 0 ; x < i ; x ++) {
for(int y = 0 ; y <= b ; y ++) {
ndp[x][y] += dp[x][y];
}
for(int y = 0 ; y <= b-vec[i] ; y ++) {
ndp[x+1][y + vec[i]] += dp[x][y] * (x+1) / (n-x);
}
}
dp = ndp;
}
db ans = 0;
for(int i = 0 ; i < n ; i ++) {
ndp = dp;
for(int x = 0 ; x < n ; x ++) {
for(int y = 0 ; y <= b-vec[i] ; y ++) {
ndp[x+1][y+vec[i]] -= ndp[x][y] * (x+1) / (n-x);
}
}
for(int x = 0 ; x < n ; x ++) {
for(int y = max(0, a-vec[i]+1) ; y <= min(a, b-vec[i]) ; y ++) {
ans += ndp[x][y] / (n-x);
}
}
}
cout << fixed << setprecision(50) << (long double)ans << endl;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}
詳細信息
Test #1:
score: 0
Wrong Answer
time: 1ms
memory: 3712kb
input:
5 2 4 1 1 1 5 5
output:
0.00000000000000000000000000000000000000000000000000
result:
wrong answer 1st numbers differ - expected: '0.1000000', found: '0.0000000', error = '0.1000000'