Java compressing Strings

Question

I need to create a method that receives a String and also returns a String.

Ex input: AAABBBBCC

Ex output: 3A4B2C

Well, this is quite embarrassing a

Answer 1

• use StringBuilder (you did that)
• define two variables - previousChar and counter
• loop from 0 to str.length() - 1
• each time get str.charat(i) and compare it to what's stored in the previousChar variable
• if the previous char is the same, increment a counter
• if the previous char is not the same, and counter is 1, increment counter
• if the previous char is not the same, and counter is >1, append counter + currentChar, reset counter
• after the comparison, assign the current char previousChar
• cover corner cases like "first char"

Something like that.