package edu.java.chap1;

/*

* simple string compress

* input: aaabbbccc

* output:a3b3c3

* if output is longer than input, then return input instead.

*/

public class StringCompress {

public static void Stringbuffer(){

StringBuffer sb = new StringBuffer();

sb.append(1);

System.out.println(sb.toString());

}

//time complex: O(n), space complex: O(n)

public static void compress1(String str){

if(str.length() == 0) {

System.out.println("please enter a string longer than 0 length");

return;

}

char pos = str.charAt(0);

int num = 0;

StringBuffer sb = new StringBuffer();

for(int i = 0; i<str.length();i++){

if(str.charAt(i) == pos){

num++;

}

else{

sb.append(pos);

sb.append(num);

pos = str.charAt(i);

num = 1;

}

}

sb.append(pos);

sb.append(num);

String result = sb.toString();

if(result.length()>str.length()){

System.out.println(str);

}else{

System.out.println(result);

}

}

public static void main(String[] args) {

String str = "aaabbbcccddd";

//String str2 = "abcdefg";

compress1(str);

}

}