Add Set Kth Bit (TheAlgorithms#4990)

inishantjain · web-flow · commit a7d140a43e03 · 2024-01-02T20:18:01.000+02:00
diff --git a/src/main/java/com/thealgorithms/bitmanipulation/SetKthBit.java b/src/main/java/com/thealgorithms/bitmanipulation/SetKthBit.java
@@ -0,0 +1,22 @@
+package com.thealgorithms.bitmanipulation;
+
+/***
+ * Sets the kth bit of a given integer to 1
+ * e.g. setting 3rd bit in binary of 17 (binary 10001) gives 25 (binary 11001)
+ * @author inishantjain
+ */
+
+public class SetKthBit {
+    /**
+     * Sets the kth bit of a given integer.
+     *
+     * @param num The original integer.
+     * @param k   The position of the bit to set (0-based index).
+     * @return The integer with the kth bit set.
+     */
+    public static int setKthBit(int num, int k) {
+        int mask = 1 << k;
+        num = num | mask;
+        return num;
+    }
+}
diff --git a/src/test/java/com/thealgorithms/bitmanipulation/SetKthBitTest.java b/src/test/java/com/thealgorithms/bitmanipulation/SetKthBitTest.java
@@ -0,0 +1,23 @@
+package com.thealgorithms.bitmanipulation;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class SetKthBitTest {
+
+    @Test
+    void testSetKthBit() {
+        // Test case: Setting the 0th bit in 5 (binary 101)
+        assertEquals(5, SetKthBit.setKthBit(5, 0));
+
+        // Test case: Setting the 2nd bit in 10 (binary 1010)
+        assertEquals(14, SetKthBit.setKthBit(10, 2));
+
+        // Test case: Setting the 3rd bit in 15 (binary 1111)
+        assertEquals(15, SetKthBit.setKthBit(15, 3));
+
+        // Test case: Setting the 1st bit in 0 (binary 0)
+        assertEquals(2, SetKthBit.setKthBit(0, 1));
+    }
+}
