Find four elements that sum to a given value | Set 1 ( n ^ 3 solution ) |  ; A naive solution to print all combination of 4 elements in A [ ] with sum equal to X ; Fix the first element and find other three ; Fix the second element and find other two ; Fix the third element and find the fourth ; find the fourth ; Driver program to test above functions
class FindFourElements { void findFourElements ( int A [ ] , int n , int X ) { for ( int i = 0 ; i < n - 3 ; i ++ ) { for ( int j = i + 1 ; j < n - 2 ; j ++ ) { for ( int k = j + 1 ; k < n - 1 ; k ++ ) { for ( int l = k + 1 ; l < n ; l ++ ) { if ( A [ i ] + A [ j ] + A [ k ] + A [ l ] == X ) System . out . print ( A [ i ] + " ▁ " + A [ j ] + " ▁ " + A [ k ] + " ▁ " + A [ l ] ) ; } } } } } public static void main ( String [ ] args ) { FindFourElements findfour = new FindFourElements ( ) ; int A [ ] = { 10 , 20 , 30 , 40 , 1 , 2 } ; int n = A . length ; int X = 91 ; findfour . findFourElements ( A , n , X ) ; } }