mirror of
https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
56 lines
1.2 KiB
C++
56 lines
1.2 KiB
C++
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#include<iostream>
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using namespace std;
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#define N 2005
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double a[7],b[7],dp[N][N];
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double pa,pb,ptie;
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int hp1,hp2;
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int main()
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{
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int i,j;
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while(scanf("%d%d",&hp1,&hp2)!=EOF)
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{
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swap(hp1,hp2);
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for(i=1;i<=6;i++)
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scanf("%lf",&a[i]);
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for(i=1;i<=6;i++)
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scanf("%lf",&b[i]);
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pa=pb=0;
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for(i=2;i<=6;i++)
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{
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for(j=1;j<=i-1;j++)
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{
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pa+=a[i]*b[j];
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pb+=a[j]*b[i];
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}
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}
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ptie=1-pa-pb;
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if(ptie!=1)
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{
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pa=pa/(1-ptie);
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pb=pb/(1-ptie);
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}
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//dp[i][j]->probability of A won i,B won j
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dp[0][0]=1;
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for(i=0;i<hp2;i++)
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{
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for(j=0;j<=hp1;j++)
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{
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if(i||j)
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{
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dp[i][j]=0;
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if(i)
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dp[i][j]+=dp[i-1][j]*pa;
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if(j)
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dp[i][j]+=dp[i][j-1]*pb;
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}
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}
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}
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double ans=0;
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for(i=0;i<hp1;i++)
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ans+=dp[hp2-1][i]*pa;
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if(ans>1)
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ans=1;
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printf("%.6lf\n",ans);
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}
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}
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