#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <cctype>
#include <cassert>
#include <limits>
#include <functional>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
#if defined(_MSC_VER) || __cplusplus > 199711L
#define aut(r,v) auto r = (v)
#else
#define aut(r,v) __typeof(v) r = (v)
#endif
#define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it)
#define all(o) (o).begin(), (o).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
using namespace std;
typedef vector<int> vi; typedef pair<int, int> pii; typedef vector<pair<int, int> > vpii; typedef long long ll;
template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }


template<typename T>T gcd_positive(T x, T y) { return y == 0 ? x : gcd_positive(y, x%y); }
template<typename T>T gcd(T x, T y) { return gcd_positive(abs(x), abs(y)); }

struct Ratio {
	typedef ll T;
	T x, y;
	Ratio() : x(0), y(1) {}
	Ratio(T x_) : x(x_), y(1) {}
	Ratio(T x_, T y_) : x(x_), y(y_) { normalize(); }
	void normalize() {
		T g = gcd(x, y);
		x = x / g; y = y / g;
		if(x < 0 && y < 0) x = -x, y = -y;
	}
	Ratio& operator*=(const Ratio& q) {
		x = x*q.x, y = y*q.y; normalize();
		return *this;
	}
	Ratio& operator/=(const Ratio& q) {
		x = x*q.y, y = y*q.x; normalize();
		return *this;
	}
	Ratio operator*(const Ratio& q) const { return Ratio(*this) *= q; }
	Ratio operator/(const Ratio& q) const { return Ratio(*this) /= q; }
	Ratio operator-() const { return Ratio(-x, y); }
	bool isinteger() const { return y == 1; }
};
ostream& operator<<(ostream &o, const Ratio& p) { o << p.x << "/" << p.y; return o; }
ll lcm(ll x, ll y) { return x / gcd(x, y)*y; }
Ratio lcm(const Ratio &a, const Ratio &b) {
	return Ratio(lcm(a.x, b.x), gcd(a.y, b.y));
}
Ratio getPeriod(const vi &ps) {
	int n = ps.size();
	Ratio r(1, 0);
	rep(i, n) reu(j, i + 1, n)
		r = lcm(r, Ratio(abs((ll)ps[i] * ps[j]), abs(ps[i] - ps[j])));
	return r;
}

int main() {
	int T1; int T2; int T3;
	while(~scanf("%d%d%d", &T1, &T2, &T3)) {
		vi ps = {T1, T2, T3};
		auto ans = getPeriod(ps);
		printf("%lld/%lld\n", ans.x, ans.y);
	}
	return 0;
}