def calp(index,l,r): 计算所有区间都大于等于index的概率 pi=1 for i in range(len(l)): lennums=r[i]-l[i]+1 if r[i]<index: return 0 elif index<l[i]: pass else: temp=(r[i]-index+1)/lennums pi*=temp return pi def cal_index_p(index,l,r): 计算index为最小值的概率 return (calp(index,l,r)-calp(index+1,l,r)) def cal_e(n,l,r): min_num=min(l) max_num=max(r) res=0 for i in range(min_num,max_num+1): res+=cal_index_p(i,l,r)*i return res