第二种定义：可以沉默，但永不犯错 In the second approach to defining Las Vegas algorithms we allow the an- swer"?"15 We say that a randomized algorithm A is a Las Vegas algorithm computing a problem F if for every input instance x of F, 保持沉默但 Pob(A(z)=F()之2， 永不犯错 and Pw4@=y=1-Pnob4)=Fe》≤分 In this second approach one may consider TimeA(n)as the time complex- ity of A because the nature of this second approaeh is to stop after TimeA() the (worst case)time complexity of A is TimeA(n)=max{TimeA(x)Ix is an input of size n}第二种定义：可以沉默，但永不犯错 保持沉默但 永不犯错