will contain max product
let max_product = Number . MIN_VALUE ; for ( let i = 0 ; i < n - 3 ; i ++ ) for ( let j = i + 1 ; j < n - 2 ; j ++ ) for ( let k = j + 1 ; k < n - 1 ; k ++ ) for ( let l = k + 1 ; l < n ; l ++ ) max_product = Math . max ( max_product , arr [ i ] * arr [ j ] * arr [ k ] * arr [ l ] ) ; return max_product ; }