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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
#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;
}

详细

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
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021789
866021...

result: