概率期望谔谔谔。#include<bits/stdc++.h>usingnamespacestd;doublef[1010][1010];doubleg[1010][1010];doubleC[1010][1010];intmain(){ intn=ri,d=ri,r=ri; C[0][0]=1; for(inti=1;i<=n;i++){ C[i][0]=1; for(intj=1;j<=