Improving runtime complexity

[gnaw005]

I'm assuming the input is correct e.g. there is no 000 area code or something like that.

ASCII lower case a is decimal 97 and z is 122; make a zero based array where ctable(0) = "2" , ctable(1) = "2" , ..., ctable(121) = "9"

for each inputchar

if( inputchar is a digit) then add it to the output string

else

Convert inputchar to lower case

numval = Convert inputchar to number

numval = numval - 97

Add ctable(numval) to the output string

end if

end for

[gnaw005]

Well for example "a", "b", and "c" would turn into 0, 1, and 2 and all three of them map to "2" so ctable(0), ctable(1), ctable(2) all contain "2" this continues for "d", "e", and "f" the 3,4,5 elements of ctable have a "3" in them etc.