TOPCORDER SRM598 DIV1

The Question is

Problem Statement
	Fox Ciel received a string as a birthday present. However, the string was too long for her, so she decided to make it shorter by erasing some characters. The erasing process will look as follows: Find the smallest i such that the i-th character and the (i+1)-th character of the string are same. If there is no such i, end the process. Remove the i-th and the (i+1)-th character of the string, and repeat from 1. For example, if she receives "cieeilll", she will change the string as follows: "cieeilll" -> "ciilll" -> "clll" -> "cl". You are given a String s. Return the string she will get after she erases characters as described above.
Definition
	Class: ErasingCharacters Method: simulate Parameters: String Returns: String Method signature: String simulate(String s) (be sure your method is public)
Limits
	Time limit (s): 2.000 Memory limit (MB): 64
Constraints
-	s will contain between 1 and 50 characters, inclusive.
-	Each character in s will be a lowercase letter ('a'-'z').
Examples
0)
	"cieeilll" Returns: "cl" This is the example from the statement.
1)
	"topcoder" Returns: "topcoder" She won't erase any characters at all.
2)
	"abcdefghijklmnopqrstuvwxyyxwvutsrqponmlkjihgfedcba" Returns: ""
3)
	"bacaabaccbaaccabbcabbacabcbba" Returns: "bacbaca"
4)
	"eel" Returns: "l"

My Solution is Below

public static String simulate(String str){
  int start =0;
 
  while(str.length()-1 >start){
   char firstChar = str.charAt(start);
//   System.out.println(firstChar + " : fisrt");
   char nextChar = str.charAt(start+1);
//   System.out.println(nextChar +" : next");
   if(firstChar == nextChar){
    str = str.substring(0, start) + str.substring(start+2, str.length());
//    System.out.println("complete:" + str);
    if(start !=0){
     start--;
    }
   }else{
    start++;
   }
  }
 
//  System.out.println(str);
  return str;
 }


## Access Logic ##


my access is below but i don't think this is a good sample

because i just got 144point / 250 point

so other soultions are better than my solution

i attached other solution after my solution

cieeilll

first point is c
first+1 point is i

c and i is differenct so first point will be 2

first point is i
first+1 point is e

c and i is differenct so first point will be 3

firtst point e
first+1 point is e

e and e is the same so cut before first point "ci" and cut after firstPoint +1 to end "ill"
and concat before string and after string

this will be ciill

first point changed first-1



Otheres are Below

public static String simulate(String s){
  for(int i=0; i<s.length()-1 i++){
    if(s.charAT(i) == s.charAT(i+1)){
     s= s.substring(0, i) + s.substring(i+2, s.length);
     i=-1;
     }
  }
}



sombody use StringBuffer.delete

and sombody use Stack

many different way i learend from topcoder --V