第二题写了On import java.util.*; public class Main { private static int[] getAns(String s,int left,int right){ if (s.charAt(left)==s.charAt(right)){ return new int[]{left,right-1,left+1,right}; }else { int newLeft=left,newRight=right; while (s.charAt(newLeft)!=s.charAt(right)) newLeft++; int len1=right-newLeft; while (s.charAt(newRight)!=s.charAt(left)) newRight--; int len2=newRight-left; return len1>len2?getAns(s,newLeft,right):getAns(s,left,newRight); } } public static void main(String[] args) { Scanner in = new Scanner(System.in); String s=in.next(); int[] ans=getAns(s,0,s.length()-1); for (int an : ans) { System.out.print(++an+" "); } } }