QOJ.ac

QOJ

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
#423280#2834. NonsenseTianTian2008RE 19ms84528kbC++141.5kb2024-05-27 22:04:042024-05-27 22:04:04

Judging History

你现在查看的是最新测评结果

  • [2024-05-27 22:04:04]
  • 评测
  • 测评结果:RE
  • 用时:19ms
  • 内存:84528kb
  • [2024-05-27 22:04:04]
  • 提交

answer

#include <iostream>
#include <cstdio>
#define mod 998244353
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pr;
ll n,m,x,y,q,fac[10010],inv[10010],px[10010],py[10010];
pr a[200001];
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;
}
void init() {
	ll t=min(m<<1|1,n+1);
	fac[0]=1;
	for(int i=1;i<=t;++i) fac[i]=fac[i-1]*(n-i+2)%mod;
	ll pro=1;
	for(int i=1;i<=t;++i) pro=pro*i%mod;
	inv[t]=ksm(pro,mod-2);
	for(int i=t;i>=1;--i) inv[i-1]=inv[i]*i%mod;
	px[t]=ksm(x,n+1-t);
	for(int i=t;i>=1;--i) px[i-1]=px[i]*x%mod;
	py[t]=ksm(y,n+1-t);
	for(int i=t;i>=1;--i) py[i-1]=py[i]*y%mod;
}
inline ll binom(ll x) {return fac[x]*inv[x]%mod;}
namespace sol1 {
	ll f[5010][5010];
	void work() {
		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)*py[j]%mod;
				else f[i][j]=-f[i-1][j];
				if(j==0) f[i][j]+=binom(i)*px[i]%mod;
				else f[i][j]+=f[i][j-1];
				f[i][j]=f[i][j]*div%mod;
			}
		for(int i=1;i<=q;++i) printf("%lld\n",(f[a[i].first][a[i].second]+mod)%mod);
	}
}
namespace sol2 {
	void work() {
		for(int i=1;i<=q;++i) printf("%lld\n",px[a[i].first+a[i].second+1]*binom(a[i].first+a[i].second+1));
	}
}
int main() {
	while(scanf("%lld%lld%lld%lld",&n,&x,&y,&q)!=EOF) {
		m=0;
		for(int i=1;i<=q;++i) {
			scanf("%lld%lld",&a[i].first,&a[i].second);
			m=max(m,max(a[i].first,a[i].second));
		}
		m=min(m<<1|1,n+1);
		init();
		if(x!=y) sol1::work();
		else sol2::work();
	}
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 5968kb

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: 0
Accepted
time: 19ms
memory: 84528kb

input:

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

output:

381781645
1
1

result:

ok 3 lines

Test #3:

score: -100
Runtime Error

input:

1000000000 998244351 998244352 1
5000 5000

output:


result: