1 public int FindFirstRepeadWord(String str) { 2 //记录重复出现的位置 3 int position = -1; 4 int length = str.length(); 5 if (length == 1){ 6 return position; 7 } 8 for (int i = 0; i < length; i++) { 9 //获取字符串的第一个字符 10 char c=str.charAt(i); 11 //查找c重复出现的位置,-1表示没有重复出现 12 int a = str.indexOf(c, i + 1); 13 if (a != -1) { 14 position = i; 15 String s = str.substring(0,a); 16 //继续深入判断是否还有重复的字符 17 int k = FindFirstRepeadWord(s); 18 if (k != -1) 19 position = k; 20 break; 21 } 22 } 23 return position; 24 }