folder structure formatted

Author: GouravRusiya30

May-LeetCoding-Challenge/Day-1-First-Bad-Version.java renamed to Java/May-LeetCoding-Challenge/Day-1-First-Bad-Version.java

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+# [May 31 Day Coding Challenge](https://leetcode.com/explore/challenge/card/may-leetcoding-challenge/)
+

May-LeetCoding-Challenge/Day-2-Jewels-and-Stones.java renamed to Java/May-LeetCoding-Challenge/Day-2-Jewels-and-Stones.java

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+/**
+ * Given a non-empty array of integers, every element appears twice except for
+ * one. Find that single one.
+ * 
+ * Note:
+ * 
+ * Your algorithm should have a linear runtime complexity. Could you implement
+ * it without using extra memory?
+ * 
+ * Example 1:
+ * 
+ * Input: [2,2,1] Output: 1
+ * 
+ * Example 2:
+ * 
+ * Input: [4,1,2,1,2] Output: 4
+ *
+ */
+class Solution {
+	public int singleNumber(int[] nums) {
+		int aloneNum = nums[0];
+
+		for (int i = 1; i < nums.length; i++) {
+			aloneNum ^= nums[i];
+			// System.out.println(aloneNum);
+		}
+
+		return aloneNum;
+	}
+}