QOJ.ac
QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#179189 | #6884. Number Table | PPP# | AC ✓ | 1ms | 3620kb | C++17 | 1.8kb | 2023-09-14 19:21:51 | 2023-09-14 19:21:52 |
Judging History
answer
#ifdef DEBUG
//#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
//const ll mod = 1000000007;
const ll mod = 998244353;
#define X first
#define Y second
ll pew(ll a, ll b)
{
ll res = 1;
while (b>0)
{
if (b&1) res = res*a%mod;
b >>= 1;
a = a*a%mod;
}
return res;
}
void solve()
{
ll n, k;
cin >> n >> k;
ll mn = mod;
if (k<30) mn = (1<<k);
ll mx = 80;
vector<vector<ll>> C(mx+1,vector<ll>(mx+1));
for (ll i=0;i<=mx;i++)
{
C[i][0] = C[i][i] = 1;
for (ll j=1;j<i;j++) C[i][j] = (C[i-1][j]+C[i-1][j-1])%mod;
}
ll Q = pew(2,k);
if (mn==mod) Q += mod;
vector<ll> dp(n+1);
for (ll i=0;i<=n;i++)
{
for (ll j=0;j<=i;j++)
{
ll x = 1;
if (j%2!=0) x = mod-1;
x = x*C[n][i]%mod;
x = x*C[i][j]%mod;
for (ll w=0;w<i-j;w++) x = x*(n-j-w)%mod;
dp[i] = (dp[i]+x)%mod;
}
}
vector<ll> f(2*n+1);
f[0] = 1;
for (ll i=2;i<=2*n;i+=2)
{
f[i] = 1;
for (ll w=0;w<i-1;w++) f[i] = f[i]*(Q-w)%mod;
if (Q<i-2) continue;
f[i] -= (f[i-2]*(Q-(i-2)))%mod*(i-1)%mod;
f[i] %= mod;
}
ll A = 0;
for (ll a=0;a<=n;a++)
{
ll x = dp[a]*f[2*n-2*a]%mod;
if (2*n-2*a>Q) continue;
for (ll w=2*n-2*a;w<2*n-a;w++) x = x*(Q-w)%mod;
A = (A+x)%mod;
}
if (A<0) A += mod;
cout << A << "\n";
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
//#ifdef DEBUG
//freopen("input.txt", "r", stdin);
//#endif
int T = 1;
cin >> T;
while (T--) solve();
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 1ms
memory: 3620kb
input:
10 1 1 2 1 2 2 3 3 5 3 10 10 10 15 10 20 39 3912 40 4512
output:
0 2 36 8736 2876160 904592472 797736012 373557465 587036386 203956590
result:
ok 10 lines