What is an efficient way to replace list of strings with another list in Unix file?

Question

Suppose I have two lists of strings (list A and list B) with the exact same number of entries, N, in each list, and I want to replace all occurrences of the the nth element

Answer 1

I needed to do something similar, and I wound up generating sed commands based on a map file:

$ cat file.map
abc => 123
def => 456
ghi => 789

$ cat stuff.txt
abc jdy kdt
kdb def gbk
qng pbf ghi
non non non
try one abc

$ sed `cat file.map | awk '{print "-e s/"$1"/"$3"/"}'`<<<"`cat stuff.txt`"
123 jdy kdt
kdb 456 gbk
qng pbf 789
non non non
try one 123

Make sure your shell supports as many parameters to sed as you have in your map.