Given ~a,b,c,d~ find a fraction ~\frac{p}{q}~ with minimum ~q~, and satisfied ~\frac{a}{b}~ ~<~ ~\frac{p}{q}~ ~<~ ~\frac{c}{d}~ .

Input

• For each test case, one line contains four integers a,b,c,d .

  Dataset 1: ~a,b,c,d~ ( 1 ~\le~ ~a,b,c,d~ ~\le~ ~1e9~, and ~\frac{a}{b}~ ~<~ ~\frac{c}{d}~ )

Output

• For each test case, print the fraction(see the sample for details).If multiple solution exists, output the one with minimum ~p~.

Sample Input

1 3 1 2
2 1 3 1
2 1 4 1
1000 1001 1001 1002

Sample Output

2/5
5/2
3/1
2001/2003