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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 |
---|---|---|---|---|---|---|---|---|---|
#417359 | #6736. Alice and Bob | ericmegalovania# | AC ✓ | 650ms | 81296kb | C++20 | 1.3kb | 2024-05-22 17:55:46 | 2024-05-22 17:55:47 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
//#define ONLINE
#ifndef ONLINE
#define debug(...) fprintf(stderr,##__VA_ARGS__)
#else
#define debug(...) ;
#endif
using LL=long long;
using PII=pair<int,int>;
template<typename T>
inline T READ(){
T x=0; bool f=0; char c=getchar();
while(!isdigit(c)) f|=(c=='-'),c=getchar();
while(isdigit(c)) x=x*10+c-'0',c=getchar();
return f?-x:x;
}
inline int read(){return READ<int>();}
inline LL readLL(){return READ<LL>();}
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
const int mod=998244353;
LL ksm(LL a,LL b){
a%=mod; LL ret=1;
while(b){
if(b&1) ret=ret*a%mod;
a=a*a%mod;
b>>=1;
}
return ret;
}
namespace Fac{//factorial
vector<LL>fc;
void init(int N){
fc.resize(N);
fc[0]=1;
for(int i=1;i<N;i++){
fc[i]=fc[i-1]*i%mod;
}
}
LL F(const int& x){
return fc[x];
}
LL P(const int& x,const int& y){
if(y>x) return 0;
return fc[x]*ksm(fc[x-y],mod-2)%mod;
}
}
int main(){
int n=read(); LL ans=0;
Fac::init(n+1);
for(int i=1;i<=n;i++){
ans=(ans+(Fac::P(n-i,i-1)*Fac::F(n-i)%mod))%mod;
}
printf("%lld",ans);
return 0;
}
/* stuff you should look for
* int overflow, array bounds
* special cases (n=1?)
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3640kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3788kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3836kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 3708kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3808kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3820kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3684kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3672kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 3704kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 3824kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3844kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 3748kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 3648kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 82ms
memory: 13932kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 489ms
memory: 62560kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 524ms
memory: 66628kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 397ms
memory: 51204kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 227ms
memory: 30500kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 445ms
memory: 57388kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 186ms
memory: 25784kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 650ms
memory: 81144kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 646ms
memory: 81296kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 647ms
memory: 81184kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"