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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#265622 | #7753. Energy Distribution | ucup-team022# | WA | 2ms | 4032kb | C++17 | 1.3kb | 2023-11-25 19:53:18 | 2023-11-25 19:53:18 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long double db;
typedef pair<int, int> pr;
int n, pl[12];
db a[12][12], mxans = 0, b[12];
int main() {
cin >> n;
for (int i = 1; i <= n; i++) {
pl[i] = i;
for (int j = 1; j <= n; j++) cin >> a[i][j];
}
do {
memset(b, 0, sizeof(b));
b[pl[1]] = 1;
// cout << 1 << '\n';
db W = 0;
for (int i = 2; i <= n; i++) {
db A = W, B = 0;
for (int k = 1; k <= n; k++) {
A -= a[pl[i]][k] * b[k];
B += a[pl[i]][k] * b[k];
}
// cout << A << ' ' << B << ' ';
if (fabs(A) < 1e-10) {
if (B > 0) {
b[pl[i]] = 0;
} else {
memset(b, 0, sizeof(b));
b[pl[i]] = 1;
}
W = 0;
for (int j = 1; j <= n; j++) {
for (int k = j + 1; k <= n; k++) {
W += b[j] * b[k] * a[j][k];
}
}
mxans = max(mxans, W);
continue;
}
db best = -B / A / 2;
best = min((db)1, max(best, (db)0));
for (int k = 1; k <= n; k++) b[k] *= best;
b[pl[i]] = 1 - best;
// cout << b[pl[i]] << '\n';
W = 0;
for (int j = 1; j <= n; j++) {
for (int k = j + 1; k <= n; k++) {
W += b[j] * b[k] * a[j][k];
}
}
mxans = max(mxans, W);
}
// puts("");
} while (next_permutation(pl + 1, pl + n + 1));
printf("%.10Lf\n", mxans);
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 3860kb
input:
2 0 1 1 0
output:
0.2500000000
result:
ok found '0.2500000', expected '0.2500000', error '0.0000000'
Test #2:
score: 0
Accepted
time: 0ms
memory: 3952kb
input:
3 0 2 1 2 0 2 1 2 0
output:
0.5714285714
result:
ok found '0.5714286', expected '0.5714290', error '0.0000004'
Test #3:
score: 0
Accepted
time: 0ms
memory: 3976kb
input:
3 0 1 2 1 0 1 2 1 0
output:
0.5000000000
result:
ok found '0.5000000', expected '0.5000000', error '0.0000000'
Test #4:
score: 0
Accepted
time: 0ms
memory: 4032kb
input:
4 0 3 1 0 3 0 1 0 1 1 0 2 0 0 2 0
output:
0.7500000000
result:
ok found '0.7500000', expected '0.7500000', error '0.0000000'
Test #5:
score: 0
Accepted
time: 0ms
memory: 3852kb
input:
5 0 0 0 4 4 0 0 2 0 4 0 2 0 2 0 4 0 2 0 0 4 4 0 0 0
output:
1.0000000000
result:
ok found '1.0000000', expected '1.0000000', error '0.0000000'
Test #6:
score: 0
Accepted
time: 1ms
memory: 3856kb
input:
6 0 9 5 5 10 6 9 0 0 0 0 1 5 0 0 0 3 0 5 0 0 0 10 5 10 0 3 10 0 0 6 1 0 5 0 0
output:
2.8571428571
result:
ok found '2.8571429', expected '2.8571430', error '0.0000001'
Test #7:
score: -100
Wrong Answer
time: 2ms
memory: 3960kb
input:
7 0 0 0 0 50 10 45 0 0 0 0 0 3 1 0 0 0 0 0 4 16 0 0 0 0 44 0 0 50 0 0 44 0 37 6 10 3 4 0 37 0 2 45 1 16 0 6 2 0
output:
12.5048076923
result:
wrong answer 1st numbers differ - expected: '12.5115850', found: '12.5048077', error = '0.0005417'