from math import gcd
from functools import reduce
from sys import stdin, stdout
input = lambda: stdin.readline().rstrip()
write = stdout.write

def main():
    T = list(map(int, stdin.read().splitlines()))

    lcm = lambda x, y: x * y // gcd(x, y)
    lcm_ = reduce(lcm, T)

    loop = []
    for i in T:
        loop.append(lcm_ // i)

    den = 1
    for i in range(1, max(loop) + 1):
        mod = []
        for j in loop:
            mod.append(j % i)
        if mod[0] == mod[1] == mod[2]:
            den = i
    ans = str(lcm_) + '/' + str(den) + '\n'
    write(ans)

main()