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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#541572 | #8942. Sugar Sweet 3 | ucup-team3510# | WA | 367ms | 5468kb | C++20 | 2.4kb | 2024-08-31 20:03:27 | 2024-08-31 20:03:27 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int mod = 1e9 + 7, N = 505;
int fac[N], inv[N], iv[N], F[N][N], G[N][N], H[N], X[N], Y[N];
int qpow(int x, int y)
{
int ans = 1;
while(y)
{
if(y & 1)
ans = (ll)ans * x % mod;
x = (ll)x * x % mod;
y >>= 1;
}
return ans;
}
void prep(int n)
{
int i;
fac[0] = 1;
for(i = 1; i <= n; i++)
fac[i] = (ll)fac[i - 1] * i % mod;
inv[n] = qpow(fac[n], mod - 2);
for(i = n; i >= 1; i--)
inv[i - 1] = (ll)inv[i] * i % mod;
for(i = 1; i <= n; i++)
iv[i] = (ll)inv[i] * fac[i - 1] % mod;
}
int Ch(int x, int y)
{
return (x < y || y < 0) ? 0 : ((ll)fac[x] * inv[y] % mod * inv[x - y] % mod);
}
int main()
{
int A, B, C, x, i, j, k, n, u, v, w, d, ans = 0;
prep(500);
scanf("%d%d%d%d", &A, &B, &C, &x);
if((A + B + C) & 1)
{
printf("0\n");
return 0;
}
n = (A + B + C) / 2;
F[0][0] = 1;
for(i = 1; i <= n; i++)
F[1][i] = (ll)Ch(2 * i - 2, i - 1) * iv[i] % mod;
for(i = 2; i <= n; i++)
for(j = i - 1; j <= n; j++)
for(k = 1; k <= n - j; k++)
F[i][j + k] = (F[i][j + k] + (ll)F[i - 1][j] * F[1][k]) % mod;
for(i = 0; i <= n; i++)
for(j = 0; j <= n; j++)
F[i][j] = (ll)F[i][j] * inv[i] % mod;
for(i = 0; i <= n; i++)
for(j = 0; j <= n; j++)
for(k = n; k >= 0; k--)
G[i][j] = ((ll)G[i][j] * j + F[k][i]) % mod;
for(i = 0; i <= A; i++)
for(j = 0; j <= B; j++)
{
k = n - i - j;
if(k > C || k < 0)
continue;
d = 0;
for(w = 0; w <= C - k; w++)
{
v = w - (i + j - B);
u = v - (k + i - A);
if(u > A - i || u < 0)
continue;
if(v > B - j || v < 0)
continue;
d = (d + (ll)Ch(i, w) * Ch(j, u) % mod * Ch(k, v)) % mod;
}
// printf("!!%d %d %d %d\n", i, j, k, d);
for(w = 0; w <= n; w++)
H[w] = (H[w] + (ll)G[i][w] * G[j][w] % mod * G[k][w] % mod * d) % mod;
}
for(i = 0; i <= n; i++)
{
H[i] = (ll)H[i] * inv[i] % mod * inv[n - i] % mod;
if((i & 1) != (n & 1))
H[i] = mod - H[i];
}
Y[0] = 1;
for(i = 0; i <= n; i++)
for(j = i + 1; j >= 0; j--)
{
X[j] = ((j ? X[j - 1] : 0) + (ll)(mod - i) * X[j] + (ll)H[i] * Y[j]) % mod;
Y[j] = ((j ? Y[j - 1] : 0) + (ll)(mod - i) * Y[j]) % mod;
}
for(i = 0; i <= n; i++)
{
X[i] = (ll)X[i] * fac[i] % mod;
// printf("??%d\n", X[i]);
ans = (ans + (ll)X[i] * qpow(i, x)) % mod;
}
printf("%d\n", ans);
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 3980kb
input:
1 2 3 1
output:
110
result:
ok 1 number(s): "110"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3924kb
input:
4 5 7 12
output:
881078346
result:
ok 1 number(s): "881078346"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3896kb
input:
1 1 7 8
output:
0
result:
ok 1 number(s): "0"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3900kb
input:
13 26 88 45
output:
0
result:
ok 1 number(s): "0"
Test #5:
score: -100
Wrong Answer
time: 367ms
memory: 5468kb
input:
100 300 400 1515897
output:
355065582
result:
wrong answer 1st numbers differ - expected: '279831696', found: '355065582'