题解 | #密码截取#

import java.nio.charset.StandardCharsets; import java.util.Scanner;

public class Main { public static int maxDuichenABA(String str, int mid){ int result = 0; int start=mid-1; int end = mid+1; result = 1; while (start >= 0 && end < str.length()) { if (str.charAt(start) == str.charAt(end)) { result += 2; start--; end++; } else break; } return result; } public static int maxDuichenAA(String str, int mid){ int result = 0; int start=mid; int end = mid+1; if(str.charAt(mid)==str.charAt(mid+1)){ while (start>=0 && end<str.length()){ if(str.charAt(start)==str.charAt(end)) { result+=2; start--; end++; } else break; } } else result=1; return result; } public static void main(String[] args) { Scanner scanner = new Scanner(System.in); String inputString = scanner.nextLine(); int maxLen = 0; for (int i = 0; i < inputString.length()-1; i++) { int tmp = maxDuichenAA(inputString,i); if (tmp>=maxLen) maxLen=tmp; tmp = maxDuichenABA(inputString,i); if (tmp>=maxLen) maxLen=tmp; } System.out.println(maxLen); } }