剑指offer第二题 替换空格 Java实现

package fenshujs;


import java.util.Scanner;


public class Janzhioffer {
/*
 * 剑指offer第二题  替换空格
 */
public static void main(String[] args) {
// TODO Auto-generated method stub
       Scanner sc = new Scanner(System.in);
       StringBuilder sb = new StringBuilder(sc.nextLine());
       for(int i = 0;i<sb.length();i++)
       {
      if(sb.charAt(i) == 32)
      {
      sb.replace(i, i+1, "%20");
      }
       }
       System.out.println(sb);
}

}

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