917. Reverse Only Letters
阿新 • • 發佈:2018-12-13
Given a string S
, return the "reversed" string where all characters that are not a letter stay in the same place, and all letters reverse their positions.
Example 1:
Input: "ab-cd" Output: "dc-ba"
Example 2:
Input: "a-bC-dEf-ghIj" Output: "j-Ih-gfE-dCba"
Example 3:
Input: "Test1ng-Leet=code-Q!" Output:"Qedo1ct-eeLg=ntse-T!"
public String reverseOnlyLetters(String S) { StringBuffer sb = new StringBuffer(S); String letterS = ""; for (int i = S.length() - 1; i >= 0; i--) { char ch = S.charAt(i); if (Character.isLetter(S.charAt(i))) { letterS += ch; } } int p = 0; for (int i = 0; i < S.length(); i++) { if (Character.isLetter(S.charAt(i))) { sb.setCharAt(i, letterS.charAt(p++)); } } return sb.toString(); }