title: If the value of list 1 is the index of list 2, how can I sort list 1 according to the list 2 value
body: <p>Suppose there is a list a[i] which stores index value v, v is the index value of  another list b[v]. I want to according to the values of list b to sort the list a.
  For example
  a=[0,2,3,1]  b=[7,10,8,6] 
  I want the list a become a=[1,2,0,3], is there some concise way to sort list a?</p>