HDOJ--2163 Palindromes

Palindromes

Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4122    Accepted Submission(s): 2405

Problem Description

Write a program to determine whether a word is a palindrome. A palindrome is a sequence of characters that is identical to the string when the characters are placed in reverse order. For example, the following strings are palindromes: “ABCCBA”, “A”, and “AMA”. The following strings are not palindromes: “HELLO”, “ABAB” and “PPA”.

Input

The input file will consist of up to 100 lines, where each line contains at least 1 and at most 52 characters. Your program should stop processing the input when the input string equals “STOP”. You may assume that input file consists of exclusively uppercase letters; no lowercase letters, punctuation marks, digits, or whitespace will be included within each word.

Output

A single line of output should be generated for each string. The line should include “#”, followed by the problem number, followed by a colon and a space, followed by the string “YES” or “NO”.

Sample Input

ABCCBA
A
HELLO
ABAB
AMA
ABAB
PPA
STOP

Sample Output

#1: YES
#2: YES
#3: NO
#4: NO
#5: YES
#6: NO
#7: NO

import java.util.Scanner;

 class Main {

        public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int t=1;
        while(sc.hasNext()){
            String str=sc.next();
            boolean isFirst=true;
            if("STOP".equals(str)){
                return;
            }        
            System.out.print("#"+(t++)+": ");
            for(int i=0,j=str.length()-1;i<j;i++,j--){
                if(str.charAt(i)!=str.charAt(j)){                
                    isFirst=false;
                    break;
                }
            }
            if(isFirst){
                System.out.println("YES");
            }else{
                System.out.println("NO");
            }
        }
    }
}