Find maximum product of digits among numbers less than or equal to N | Function that returns the maximum product of digits among numbers less than or equal to N ; Driver code
< ? php function maxProd ( $ N ) { if ( $ N == 0 ) return 1 ; if ( $ N < 10 ) return $ N ; return max ( maxProd ( ( int ) ( $ N / 10 ) ) * ( $ N % 10 ) , maxProd ( ( int ) ( $ N / 10 ) - 1 ) * 9 ) ; } $ N = 390 ; echo maxProd ( $ N ) ; ? >