Count all prefixes of the given binary array which are divisible by x | Function to return the count of total binary prefix which are divisible by x ; Initialize with zero ; Convert all prefixes to decimal ; If number is divisible by x then increase count ; Driver code
< ? php function CntDivbyX ( $ arr , $ n , $ x ) { $ number = 0 ; $ count = 0 ; for ( $ i = 0 ; $ i < $ n ; $ i ++ ) { $ number = $ number * 2 + $ arr [ $ i ] ; if ( ( $ number % $ x == 0 ) ) $ count += 1 ; } return $ count ; } $ arr = array ( 1 , 0 , 1 , 0 , 1 , 1 , 0 ) ; $ n = sizeof ( $ arr ) ; $ x = 2 ; echo CntDivbyX ( $ arr , $ n , $ x ) ;