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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#422883#2834. NonsenseTianTian2008WA 0ms8048kbC++141.4kb2024-05-27 20:00:372024-05-27 20:00:38

Judging History

你现在查看的是最新测评结果

  • [2024-05-27 20:00:38]
  • 评测
  • 测评结果:WA
  • 用时:0ms
  • 内存:8048kb
  • [2024-05-27 20:00:37]
  • 提交

answer

#include <iostream>
#include <cstdio>
#define mod 998244353
using namespace std;
typedef long long ll;
ll n,x,y,q;
ll ksm(ll x,ll y) {
	ll res=1;
	while(y) {
		if(y&1) res=res*x%mod;
		x=x*x%mod;
		y>>=1;
	}
	return res;
}
namespace sol1 {
	ll fac[5001],inv[5001],f[5001][5001];
	inline ll binom(ll x) {return fac[x]*inv[x]%mod;}
	void work() {
		ll m=min(n,5000ll);
		fac[0]=1;
		for(int i=1;i<=m;++i) fac[i]=fac[i-1]*(n-i+2)%mod;
		ll pro=1;
		for(int i=1;i<=m;++i) pro=pro*i%mod;
		inv[m]=ksm(pro,mod-2);
		for(int i=m;i>=1;--i) inv[i-1]=inv[i]*i%mod;
		ll div=ksm(x-y,mod-2);
		for(int i=0;i<=m;++i)
			for(int j=0;j<=m;++j) {
				if(i==0) f[i][j]=-binom(j)*ksm(y,n+1-j)%mod;
				else f[i][j]=-f[i-1][j];
				if(j==0) f[i][j]+=binom(i)*ksm(x,n+1-i)%mod;
				else f[i][j]+=f[i][j-1];
				f[i][j]=f[i][j]*div%mod;
			}
		ll a,b;
		while(q--) {
			scanf("%lld%lld",&a,&b);
			printf("%lld\n",(f[a][b]+mod)%mod);
		}
	}
}
namespace sol2 {
	ll binom(ll n,ll m) {
		ll x=1,y=1;
		for(int i=1;i<=m;++i) {
			x=x*(n-i+1)%mod;
			y=y*i%mod;
		}
		return x*ksm(y,mod-2)%mod;
	}
	void work() {
		ll a,b;
		while(q--) {
			scanf("%lld%lld",&a,&b);
			if(x==0) printf("%lld\n",binom(n-a,b)*ksm(y,n-a-b)%mod);
			else printf("%lld\n",binom(n-b,a)*ksm(x,n-a-b)%mod);
		}
	}
}
int main() {
	while(scanf("%lld%lld%lld%lld",&n,&x,&y,&q)!=EOF) {
		if(x!=0&&y!=0) sol1::work();
		else sol2::work();
	}
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 8048kb

input:

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

output:

6
1
866021789

result:

ok 3 lines

Test #2:

score: -100
Wrong Answer
time: 0ms
memory: 3900kb

input:

1000000000 0 1 1
1000 1000
2 0 0 1
1 1
2 998244352 998244352 1
1 1

output:

381781645
1
0

result:

wrong answer 3rd lines differ - expected: '1', found: '0'