Mercurial > repos > rliterman > csp2
annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/opt/bbmap-39.01-1/current/fun/Palindrome.java @ 68:5028fdace37b
planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
| author | jpayne |
|---|---|
| date | Tue, 18 Mar 2025 16:23:26 -0400 |
| parents | |
| children |
| rev | line source |
|---|---|
| jpayne@68 | 1 package fun; |
| jpayne@68 | 2 |
| jpayne@68 | 3 import shared.Tools; |
| jpayne@68 | 4 |
| jpayne@68 | 5 public class Palindrome { |
| jpayne@68 | 6 |
| jpayne@68 | 7 public static void main(String[] args){ |
| jpayne@68 | 8 System.out.println(longestPalindrome(args[0])); |
| jpayne@68 | 9 } |
| jpayne@68 | 10 |
| jpayne@68 | 11 public static String longestPalindrome(String s){ |
| jpayne@68 | 12 int longestLength=0; |
| jpayne@68 | 13 int longestStart=0; |
| jpayne@68 | 14 for(int i=0; i<s.length(); i++){ |
| jpayne@68 | 15 int lenEven=palindromeLength(s, i, i+1); |
| jpayne@68 | 16 if(lenEven>longestLength){ |
| jpayne@68 | 17 longestLength=lenEven; |
| jpayne@68 | 18 longestStart=i-lenEven/2+1; |
| jpayne@68 | 19 } |
| jpayne@68 | 20 int lenOdd=palindromeLength(s, i, i); |
| jpayne@68 | 21 if(lenOdd>longestLength){ |
| jpayne@68 | 22 longestLength=lenOdd; |
| jpayne@68 | 23 longestStart=i-lenOdd/2; |
| jpayne@68 | 24 } |
| jpayne@68 | 25 } |
| jpayne@68 | 26 return s.substring(longestStart, longestStart+longestLength+1); |
| jpayne@68 | 27 } |
| jpayne@68 | 28 |
| jpayne@68 | 29 public static int palindromeLengthOdd(String s, int middle){ |
| jpayne@68 | 30 int length=1; |
| jpayne@68 | 31 int a=middle-1, b=middle+1; |
| jpayne@68 | 32 while(a>=0 && b<s.length()){ |
| jpayne@68 | 33 if(s.charAt(a)==s.charAt(b)){ |
| jpayne@68 | 34 a--; |
| jpayne@68 | 35 b++; |
| jpayne@68 | 36 length+=2; |
| jpayne@68 | 37 }else{ |
| jpayne@68 | 38 break; |
| jpayne@68 | 39 } |
| jpayne@68 | 40 } |
| jpayne@68 | 41 return length; |
| jpayne@68 | 42 } |
| jpayne@68 | 43 |
| jpayne@68 | 44 public static int palindromeLengthEven(String s, int middle){ |
| jpayne@68 | 45 int length=0; |
| jpayne@68 | 46 int a=middle, b=middle+1; |
| jpayne@68 | 47 while(a>=0 && b<s.length()){ |
| jpayne@68 | 48 if(s.charAt(a)==s.charAt(b)){ |
| jpayne@68 | 49 a--; |
| jpayne@68 | 50 b++; |
| jpayne@68 | 51 length+=2; |
| jpayne@68 | 52 }else{ |
| jpayne@68 | 53 break; |
| jpayne@68 | 54 } |
| jpayne@68 | 55 } |
| jpayne@68 | 56 return length; |
| jpayne@68 | 57 } |
| jpayne@68 | 58 |
| jpayne@68 | 59 public static int palindromeLength(String s, int a, int b){ |
| jpayne@68 | 60 while(a>=0 && b<s.length()){ |
| jpayne@68 | 61 if(s.charAt(a)!=s.charAt(b)){break;} |
| jpayne@68 | 62 a--; |
| jpayne@68 | 63 b++; |
| jpayne@68 | 64 } |
| jpayne@68 | 65 return Tools.max(0, b-a-2); |
| jpayne@68 | 66 } |
| jpayne@68 | 67 |
| jpayne@68 | 68 public static boolean isPalindrome(String s, int a, int b){ |
| jpayne@68 | 69 while(a<b){ |
| jpayne@68 | 70 if(s.charAt(a)!=s.charAt(b)){ |
| jpayne@68 | 71 return false; |
| jpayne@68 | 72 } |
| jpayne@68 | 73 } |
| jpayne@68 | 74 return true; |
| jpayne@68 | 75 } |
| jpayne@68 | 76 |
| jpayne@68 | 77 } |