Commit 1220bc2

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Merge pull request #84 from greatmerlin/Added-palindrome-problem

added palindrome problem and solution

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	`1`	`+# Palindrome with Stack and Queue`
	`2`	`+`
	`3`	`+## Use Stack and Queue to check whether a String is a palindrome`
	`4`	`+`
	`5`	`+Hint:`
	`6`	`+`
	`7`	`+Example word: dad`
	`8`	`+`
	`9`	`+ stack: push(d), push(a), push(d) : d, a, d`
	`10`	`+`
	`11`	`+ queue: add(d), add(a), add(d) : d, a, d`
	`12`	`+`
	`13`	`+ #### Examples:`
	`14`	`+`
	`15`	`+ // should return true`
	`16`	`+System.out.println(checkForPalindrome("abccba"));`
	`17`	`+// should return true`
	`18`	`+System.out.println(checkForPalindrome("Was it a car or a cat I saw?"));`
	`19`	`+// should return true`
	`20`	`+System.out.println(checkForPalindrome("I did, did I?"));`
	`21`	`+// should return false`
	`22`	`+System.out.println(checkForPalindrome("hello"));`
	`23`	`+// should return true`
	`24`	`+System.out.println(checkForPalindrome("Don't nod"));`

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	`1`	`+import java.util.LinkedList;`
	`2`	`+`
	`3`	`+public static boolean checkForPalindrome(String string) {`
	`4`	`+`
	`5`	`+ LinkedList<Character> stack = new LinkedList<Character>();`
	`6`	`+ LinkedList<Character> queue = new LinkedList<Character>();`
	`7`	`+ String lowerCase = string.toLowerCase();`
	`8`	`+`
	`9`	`+ for (int i = 0; i < lowerCase.length(); i++) {`
	`10`	`+ char c = lowerCase.charAt(i);`
	`11`	`+ if (c >= 'a' && c <= 'z') {`
	`12`	`+ queue.addLast(c);`
	`13`	`+ stack.push(c);`
	`14`	`+ }`
	`15`	`+ }`
	`16`	`+`
	`17`	`+ while (!stack.isEmpty()) {`
	`18`	`+ if (!stack.pop().equals(queue.removeFirst())) {`
	`19`	`+ return false;`
	`20`	`+ }`
	`21`	`+ }`
	`22`	`+`
	`23`	`+ return true;`
	`24`	`+ }`
	`25`	`+}`

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