import sys
input = sys.stdin.readline

from math import gcd,lcm

a=int(input())
b=int(input())
c=int(input())

LCM=lcm(a,b,c)

a=LCM//a
b=LCM//b
c=LCM//c

x=gcd(abs(b-a),abs(c-b))

gg=gcd(LCM,x)

LCM//=gg
x//=gg

print(str(LCM)+"/"+str(x))