Add Power of two problem

javaProblems/problem231/Solution.java

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+class Solution {
+    public boolean solve(int n) {
+        while (n>1 && n%2==0){
+            n = n/2;
+        }
+        return n==1;
+    }
+}

javaProblems/problem231/Test.java

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+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public class Test {
+    public static void main(String[] args) throws Exception {
+        Logger logger = Logger.getLogger(Logger.GLOBAL_LOGGER_NAME);
+        Solution solveSolution = new Solution();
+
+        int arg = 16;
+        int actualAns = true;
+
+        try {
+            int ans = solveSolution.solve(arg);
+        } catch (Exception e) {
+            logger.log(Level.SEVERE, "Runtime error");
+            System.exit(1);
+            throw new Error("Runtime Error");
+        }
+        if (actualAns != ans) {
+            logger.log(Level.SEVERE, "Wrong solution!");
+            System.exit(1);
+            throw new Exception("Wrong solution!");
+        }
+        System.out.print("Testcase passed!");
+    }
+}

javaProblems/problem231/readme.md

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+# 231.Power of Two
+The code determine if a given integer n is a power of two.
+
+```
+# Example Input
+n = 16
+
+# Example Output
+true
+```