Check if a number is Bleak | Function to get no of set bits in binary representation of passed binary no . ; Returns true if n is Bleak ; Check for all numbers ' x ' smaller than n . If x + countSetBits ( x ) becomes n , then n can 't be Bleak ; Driver Code
function countSetBits ( x ) { let count = 0 ; while ( x != 0 ) { x &= ( x - 1 ) ; count ++ ; } return count ; } function isBleak ( n ) { for ( let x = 1 ; x < n ; x ++ ) if ( x + countSetBits ( x ) == n ) return false ; return true ; } if ( isBleak ( 3 ) ) document . write ( " " + " " ) ; else document . write ( " " + " " ) ; if ( isBleak ( 4 ) ) document . write ( " " + " " ) ; else document . write ( " " + " " ) ;