java彩色瓷砖编程题分析

import java.util.Scanner;

public class repleaseColor {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String str=sc.nextLine();
    getNum(str);
  }

  private static void getNum(String str) {
    // TODO Auto-generated method stub
    char[] ch=str.toCharArray();
    int tem=0;
    int len=ch.length;
    if(len>=2){
      for(int i=1;i<len-1;i=i+2){
        if(ch[i]==ch[i-1] || ch[i]==ch[i+1]){
          tem++;
        }
      }
      if(ch[len-1]==ch[len-2] && len%2==0){
        tem++;
      }
      for(int i=2;i<len-2;i=i+2){
        if(ch[i]==ch[i-1] && ch[i]==ch[i+1] && ch[i+1]!=ch[i+2] && ch[i-1]!=ch[i-2]){
          tem--;
        }
      }
    }
    System.out.println(tem);
  }
}