Remove an element to minimize the LCM of the given array | Java implementation of the above approach ; Function to return the LCM of two numbers ; Function to return the minimum LCM after removing a single element from the given array ; Prefix and Suffix arrays ; Single state dynamic programming relation for storing LCM of first i elements from the left in Prefix [ i ] ; Initializing Suffix array ; Single state dynamic programming relation for storing LCM of all the elements having index greater than or equal to i in Suffix [ i ] ; If first or last element of the array has to be removed ; If any other element is replaced ; Return the minimum LCM ; Driver code
class GFG { static int lcm ( int a , int b ) { int GCD = __gcd ( a , b ) ; return ( a * b ) / GCD ; } static int MinLCM ( int a [ ] , int n ) { int [ ] Prefix = new int [ n + 2 ] ; int [ ] Suffix = new int [ n + 2 ] ; Prefix [ 1 ] = a [ 0 ] ; for ( int i = 2 ; i <= n ; i += 1 ) { Prefix [ i ] = lcm ( Prefix [ i - 1 ] , a [ i - 1 ] ) ; } Suffix [ n ] = a [ n - 1 ] ; for ( int i = n - 1 ; i >= 1 ; i -= 1 ) { Suffix [ i ] = lcm ( Suffix [ i + 1 ] , a [ i - 1 ] ) ; } int ans = Math . min ( Suffix [ 2 ] , Prefix [ n - 1 ] ) ; for ( int i = 2 ; i < n ; i += 1 ) { ans = Math . min ( ans , lcm ( Prefix [ i - 1 ] , Suffix [ i + 1 ] ) ) ; } return ans ; } static int __gcd ( int a , int b ) { return b == 0 ? a : __gcd ( b , a % b ) ; } public static void main ( String [ ] args ) { int a [ ] = { 5 , 15 , 9 , 36 } ; int n = a . length ; System . out . println ( MinLCM ( a , n ) ) ; } }