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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 |
---|---|---|---|---|---|---|---|---|---|
#191007 | #6736. Alice and Bob | Bbaka_# | AC ✓ | 132ms | 159936kb | C++20 | 1.1kb | 2023-09-29 16:42:18 | 2023-09-29 16:42:19 |
Judging History
answer
#include <iostream>
#include <cmath>
using namespace std;
using ll = long long;
// #define int long long
const int mod = 998244353;
const int maxn = 1e7 + 10;
ll f[maxn],g[maxn];
ll qpow(ll n, ll m)
{
n%=mod;
ll res = 1;
while(m)
{
if(m&1)
{
res = res*n%mod;
}
n = n*n%mod;
m>>=1;
}
return res;
}
void init(void)
{
f[0]=1;
for(int i=1;i<maxn;i++)
{
f[i]=f[i-1]*i%mod;
}
g[maxn-1]=qpow(f[maxn-1],mod-2);
for(int i=maxn-2;i>=1;i--)
{
g[i]=g[i+1]*(i+1)%mod;
}
}
ll C(int n, int m)
{
if(m==0||m==n)
{
return 1;
}
if(m<=0 || n < m)
{
return 0;
}
else
{
return f[n]*g[m]%mod*g[n-m]%mod;
}
}
signed main()
{
init();
int n;
cin >> n;
ll ans = 0;
for (int i = 1; i <= n; i++)
{
ans += C(n - i, i - 1) * f[i - 1] % mod * f[n - i] % mod;
ans %= mod;
}
cout << ans << '\n';
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 23ms
memory: 159936kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 73ms
memory: 159836kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 70ms
memory: 159936kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 69ms
memory: 159808kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 55ms
memory: 159840kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 69ms
memory: 159864kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 86ms
memory: 159840kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 82ms
memory: 159848kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 82ms
memory: 159844kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 61ms
memory: 159852kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 90ms
memory: 159776kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 81ms
memory: 159852kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 90ms
memory: 159904kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 89ms
memory: 159872kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 116ms
memory: 159868kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 127ms
memory: 159784kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 94ms
memory: 159804kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 107ms
memory: 159804kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 101ms
memory: 159852kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 104ms
memory: 159844kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 132ms
memory: 159840kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 94ms
memory: 159844kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 110ms
memory: 159848kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"