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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#423255#2834. NonsenseDaiRuiChen007TL 0ms0kbC++141.2kb2024-05-27 21:52:442024-05-27 21:52:44

Judging History

你现在查看的是最新测评结果

  • [2024-05-27 21:52:44]
  • 评测
  • 测评结果:TL
  • 用时:0ms
  • 内存:0kb
  • [2024-05-27 21:52:44]
  • 提交

answer

#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=5005,MAXQ=2e5+5,MOD=998244353;
ll ksm(ll a,ll b=MOD-2,ll p=MOD) {
	if(b<0) b+=MOD-1;
	ll ret=1;
	for(;b;a=a*a%p,b>>=1) if(b&1) ret=ret*a%p;
	return ret;
}
int n,q,s,t,m=0;
int a[MAXQ],b[MAXQ];
ll f[MAXN][MAXN],C[MAXN<<1];
void solve() {
	m=0;
	for(int i=1;i<=q;++i) scanf("%d%d",&a[i],&b[i]),m=max({m,a[i],b[i]});
	if(s==t) {
		C[0]=1;
		for(int i=1;i<=min(2*m,n);++i) {
			C[i]=C[i-1]*(n-i+1)%MOD*ksm(i)%MOD;
		}
		for(int i=1;i<=q;++i) printf("%lld\n",ksm(s,n-a[i]-b[i])*C[a[i]+b[i]]%MOD);
		return ;
	}
	C[0]=1;
	for(int i=1;i<=m;++i) {
		C[i]=C[i-1]*(n-i+2)%MOD*ksm(i)%MOD;
	}
	for(int i=0;i<=m;++i) for(int j=0;j<=m;++j) f[i][j]=0;
	for(int i=0;i<=m;++i) {
		f[i][0]=(f[i][0]+C[i]*ksm(s,n+1-i))%MOD;
		f[0][i]=(f[0][i]-C[i]*ksm(t,n+1-i))%MOD;
		if(f[0][i]<0) f[0][i]+=MOD;
	}
	int w=ksm((s+MOD-t)%MOD);
	for(int i=0;i<=m;++i) for(int j=0;j<=m;++j) {
		if(i) f[i][j]=(f[i][j]+MOD-f[i-1][j])%MOD;
		if(j) f[i][j]=(f[i][j]+f[i][j-1])%MOD;
		f[i][j]=f[i][j]*w%MOD;
	}
	for(int i=1;i<=q;++i) printf("%lld\n",f[a[i]][b[i]]);
}
signed main() {
	while(scanf("%d%d%d%d",&n,&s,&t,&q)) solve();
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 0
Time Limit Exceeded

input:

3 1 2 2
1 1
1 2
100 2 3 1
1 1

output:

6
1
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
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866021789
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866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021...

result: