Number of pairs of lines having integer intersection points | Count number of pairs of lines having integer intersection point ; Initialize arrays to store counts ; Count number of odd and even Pi ; Count number of odd and even Qi ; Return the count of pairs ; Driver code
function countPairs ( P , Q , N , M ) { var A = [ 0 , 0 ] , B = [ 0 , 0 ] ; for ( var i = 0 ; i < N ; i ++ ) A [ P [ i ] % 2 ] ++ ; for ( var i = 0 ; i < M ; i ++ ) B [ Q [ i ] % 2 ] ++ ; return ( A [ 0 ] * B [ 0 ] + A [ 1 ] * B [ 1 ] ) ; } var P = [ 1 , 3 , 2 ] , Q = [ 3 , 0 ] ; var N = P . length ; var M = Q . length ; document . write ( countPairs ( P , Q , N , M ) ) ;