Classifying values in vector

I have a vector of size 217 called "A".

the values of A are not sorted and range from 0 to 1 (normalized)

I am having difficulty writing a program to create a new vector "B" where

if A's value is 0< A <=0.333 then B is 0
if A's value is 0.333< A <=0.666 then B is 1
if A's value is 0.666< A <=1 then B is 2

so if A is

0.22
0.999
0.444
0

B would be

0
2
1
0

thank you,