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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#240790#6346. Record Parityylf#WA 1ms8048kbC++14892b2023-11-05 19:00:352023-11-05 19:00:35

Judging History

你现在查看的是最新测评结果

  • [2023-11-05 19:00:35]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:8048kb
  • [2023-11-05 19:00:35]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
inline int read()
{
	char ch;
	while((ch=getchar())<'0'||ch>'9');
	int res=ch-'0';
	while((ch=getchar())>='0'&&ch<='9') res=res*10+ch-'0';
	return res;
}
const int N=1000100;
const int mod=998244353;
int n,a[N],jc[N],ny[N];
int ksm(int x,int K)
{
	int res=1;
	while(K)
	{
		if(K&1) res=1ll*res*x%mod;
		K>>=1;
		x=1ll*x*x%mod;
	}
	return res;
}
int C(int n,int m)
{
	return 1ll*jc[n]*ny[n-m]%mod*ny[m]%mod;
}
int main()
{
	n=read();int K=read();
	jc[0]=1;
	for(int i=1;i<=n;i++) a[i]=read(),jc[i]=1ll*jc[i-1]*i%mod;
	ny[n]=ksm(jc[n],mod-2);
	for(int i=n-1;i>=0;i--) ny[i]=1ll*ny[i+1]*(i+1)%mod;
	int lst=0,ans=0;
	for(int i=1;i<=n;i++)
	{
		if(i==1||a[i]>a[i-1]) lst++;
		else lst=1;
		if(lst>=K) (ans+=C(lst-1,K-1))%=mod;
	}
	if(K&1) printf("%d",(mod-ans)%mod);
	else printf("%d",ans);
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 7836kb

input:

5 2
4 1 2 5 3

output:

3

result:

ok 1 number(s): "3"

Test #2:

score: 0
Accepted
time: 1ms
memory: 8048kb

input:

7 3
1 2 3 4 5 6 7

output:

998244318

result:

ok 1 number(s): "998244318"

Test #3:

score: 0
Accepted
time: 1ms
memory: 7896kb

input:

5 5
2 5 4 1 3

output:

0

result:

ok 1 number(s): "0"

Test #4:

score: -100
Wrong Answer
time: 1ms
memory: 7976kb

input:

10 3
9 7 3 6 10 4 8 2 5 1

output:

998244352

result:

wrong answer 1st numbers differ - expected: '0', found: '998244352'