Added task 762.

Author: javadev

src/main/java/g0701_0800/s0762_prime_number_of_set_bits_in_binary_representation/Solution.java

@@ -0,0 +1,35 @@
+package g0701_0800.s0762_prime_number_of_set_bits_in_binary_representation;
+
+// #Easy #Math #Bit_Manipulation
+
+public class Solution {
+    public int countPrimeSetBits(int left, int right) {
+        int count = 0;
+        boolean[] notPrime = new boolean[33];
+        notPrime[0] = true;
+        notPrime[1] = true;
+        sieve(notPrime);
+        for (int i = left; i <= right; i++) {
+            int num = i;
+            int setBits = 0;
+            while (num > 0) {
+                num = num & (num - 1);
+                setBits++;
+            }
+            if (!notPrime[setBits]) {
+                count++;
+            }
+        }
+        return count;
+    }
+
+    private void sieve(boolean[] notPrime) {
+        for (int i = 2; i <= 32; i++) {
+            if (!notPrime[i]) {
+                for (int j = 2 * i; j <= 32; j += i) {
+                    notPrime[j] = true;
+                }
+            }
+        }
+    }
+}

src/main/java/g0701_0800/s0762_prime_number_of_set_bits_in_binary_representation/readme.md

@@ -0,0 +1,45 @@
+762\. Prime Number of Set Bits in Binary Representation
+
+Easy
+
+Given two integers `left` and `right`, return _the **count** of numbers in the **inclusive** range_ `[left, right]` _having a **prime number of set bits** in their binary representation_.
+
+Recall that the **number of set bits** an integer has is the number of `1`'s present when written in binary.
+
+*   For example, `21` written in binary is `10101`, which has `3` set bits.
+
+**Example 1:**
+
+**Input:** left = 6, right = 10
+
+**Output:** 4
+
+**Explanation:**
+
+    6 -> 110 (2 set bits, 2 is prime)
+    7 -> 111 (3 set bits, 3 is prime)
+    8 -> 1000 (1 set bit, 1 is not prime)
+    9 -> 1001 (2 set bits, 2 is prime)
+    10 -> 1010 (2 set bits, 2 is prime)
+    4 numbers have a prime number of set bits. 
+
+**Example 2:**
+
+**Input:** left = 10, right = 15
+
+**Output:** 5
+
+**Explanation:**
+
+    10 -> 1010 (2 set bits, 2 is prime)
+    11 -> 1011 (3 set bits, 3 is prime)
+    12 -> 1100 (2 set bits, 2 is prime)
+    13 -> 1101 (3 set bits, 3 is prime)
+    14 -> 1110 (3 set bits, 3 is prime)
+    15 -> 1111 (4 set bits, 4 is not prime)
+    5 numbers have a prime number of set bits. 
+
+**Constraints:**
+
+*   <code>1 <= left <= right <= 10<sup>6</sup></code>
+*   <code>0 <= right - left <= 10<sup>4</sup></code>

src/test/java/g0701_0800/s0762_prime_number_of_set_bits_in_binary_representation/SolutionTest.java

@@ -0,0 +1,18 @@
+package g0701_0800.s0762_prime_number_of_set_bits_in_binary_representation;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+class SolutionTest {
+    @Test
+    void countPrimeSetBits() {
+        assertThat(new Solution().countPrimeSetBits(6, 10), equalTo(4));
+    }
+
+    @Test
+    void countPrimeSetBits2() {
+        assertThat(new Solution().countPrimeSetBits(10, 15), equalTo(5));
+    }
+}