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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 |
|---|---|---|---|---|---|---|---|---|---|
| #368579 | #6736. Alice and Bob | ryh7# | TL | 905ms | 133076kb | C++14 | 1.1kb | 2024-03-27 13:24:43 | 2024-03-27 13:24:45 |
Judging History
answer
// Problem: 小红的区间删除
// Contest: NowCoder
// URL: https://ac.nowcoder.com/acm/contest/78292/G
// Memory Limit: 524288 MB
// Time Limit: 4000 ms
//
// Powered by CP Editor (https://cpeditor.org)
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using VI = vector<int>;
using PII = pair<ll,ll>;
using VVI = vector<vector<int>>;
const ll mod = 998244353;
const ll INF = 1e18;
const int N = 1e7 + 10;
ll n,k;
ll fac[N];
ll inv[N];
ll ksm(ll a , ll b , ll mod){
ll res = 1;
while(b){
if(b % 2) res = res * a % mod;
b /= 2;
a = a * a % mod;
}
return res;
}
ll A(int n , int m){
if(m > n) return 0;
return fac[n] * inv[n - m] % mod;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin>>n;
fac[0] = 1;
inv[0] = 1;
for(int i = 1 ; i <= n ; i++){
fac[i] = fac[i - 1] * i % mod;
inv[i] = ksm(fac[i] , mod - 2 , mod);
}
ll res = 0;
for(int i = 1 ; i <= n ; i++){
res += A(n - i , i - 1) * A(n - i , n - i);
res %= mod;
}
cout<<res;
}
//5 4 3 2 1
//5 4 3 2 1
詳細信息
Test #1:
score: 100
Accepted
time: 1ms
memory: 5664kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5660kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5604kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5676kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5700kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 5752kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5704kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5612kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5612kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5612kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5700kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5728kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5664kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 153ms
memory: 27372kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 836ms
memory: 125272kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 905ms
memory: 133076kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 675ms
memory: 101168kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 394ms
memory: 63640kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 777ms
memory: 113868kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 322ms
memory: 52256kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: -100
Time Limit Exceeded
input:
9999998