Package g0701_0800.s0762_prime_number_of_set_bits_in_binary_representation

Class Solution

java.lang.Object
g0701_0800.s0762_prime_number_of_set_bits_in_binary_representation.Solution
public class Solution extends java.lang.Object
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:

  • 1 <= left <= right <= 106
  • 0 <= right - left <= 104

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    countPrimeSetBits(int left, int right)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • countPrimeSetBits

      public int countPrimeSetBits(int left, int right)