BAEL-9247 How to Check if a Number Is the Sum of Two or More Consecutive Integers

Author: yabetancourt

algorithms-modules/algorithms-numeric/src/test/java/com/baeldung/algorithms/consecutivenumbers/ConsecutiveNumbersUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.algorithms.consecutivenumbers;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class ConsecutiveNumbersUnitTest {
+
+    @Test
+    void whenIsSumOfConsecutiveUsingBruteForce_thenReturnsTrue() {
+        int n = 15;
+
+        boolean isSumOfConsecutive = false;
+        for (int k = 2; (k * (k - 1)) / 2 < n; k++) {
+            int diff = n - k * (k - 1) / 2;
+            if (diff % k == 0 && diff / k > 0) {
+                isSumOfConsecutive = true;
+                break;
+            }
+        }
+
+        assertTrue(isSumOfConsecutive);
+    }
+
+    @Test
+    void whenIsSumOfConsecutiveUsingBitwise_thenReturnsTrue() {
+        int n = 15;
+        boolean result = (n > 0) && ((n & (n - 1)) != 0);
+        assertTrue(result);
+    }
+
+}