// yukicoder: No.229 線分上を往復する3つの動点の一致
// bal4u 2019.8.25

#include <stdio.h>

typedef long long ll;

ll gcd(ll a, ll b) {
	ll r;
	while (b != 0) r = a % b, a = b, b = r;
	return a;
}

inline static void chmax(ll *a, ll b) { if (*a < b) *a = b; }

int main()
{
	int T1, T2, T3; ll T, ma = 0;

	scanf("%d%d%d", &T1, &T2, &T3);
	T = (ll)T1*T2*T3;
	
	chmax(&ma, gcd((T3-T1)*T2, (T3-T2)*T1));
	chmax(&ma, gcd((T3-T1)*T2, (T3+T2)*T1));
	chmax(&ma, gcd((T3+T1)*T2, (T3-T2)*T1));
	chmax(&ma, gcd((T3+T1)*T2, (T3+T2)*T1));

	printf("%lld/%lld\n", T/gcd(T,ma), ma/gcd(T,ma));
	return 0;
}