#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<cstdlib>
#include<algorithm>
#include<bitset>
#include<vector>
#include<list>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<sstream>
#include<fstream>
#include<iomanip>
#include<ctime>
#include<complex>
#include<functional>
#include<climits>
#include<cassert>
#include<iterator>
#include<unordered_map>
using namespace std;
#define MOD 1000000007
namespace math{
	long long int gcd(long long int a, long long int b){
		if (a > b){
			swap(a, b);
		}
		while (a){
			swap(a, b);
			a %= b;
		}
		return b;
	}
	long long int lcm(long long int a, long long int b){
		long long int g =gcd(a, b);
		a /= g;
		return a*b;
	}
	long long int ppow(long long int i, long long int j){
		long long int res = 1LL;
		while (j){
			if (j & 1LL){
				res *= i;
				res %= MOD;
			}
			i *= i;
			i %= MOD;
			j >>= 1LL;
		}
		return res;
	}
	long long int extgcd(long long int a, long long int b, long long int &x, long long int &y){
		long long int d = a;
		if (b != 0){
			d = extgcd(b, a%b, y, x);
			y -= (a / b)*x;
		}
		else{
			x = 1;
			y = 0;
		}
		return d;
	}
	long long int modinverse(long long int a, long long int b){   //aの逆元を求める(mod b)
		long long int x, y;
		long long int d = extgcd(a, b, x, y);
		return (x%b + b) % b;
	}
	namespace matrix{
		vector<vector<long long int> > mul(vector<vector<long long int> > &a, vector<vector<long long int> > &b){
			vector<vector<long long int> > c(a.size(), vector<long long int>(b[0].size()));
			for (int i = 0; i < a.size(); i++){
				for (int j = 0; j < b.size(); j++){
					for (int k = 0; k < b[0].size(); k++){
						c[i][k] = (c[i][k] + a[i][j] * b[j][k]);
						c[i][k] %= MOD;
					}
				}
			}
			return c;
		}
		vector<vector<long long int> > ppow(vector<vector<long long int> > a, long long int n){
			vector<vector<long long int> > b = a;
			if (n == 1LL){
				return b;
			}
			n--;
			while (n){
				if ((n & 1LL)){
					b = mul(b, a);
				}
				a = mul(a, a);
				n >>= 1LL;
			}
			return b;
		}
	}
	namespace fibonacci{
		/*
		index :1,2,3,4,5,6,
		number:1,1,2,3,5,8,
		*/
		vector<vector<long long int> > mat;
		long long int get_fibonacci(long long int a){  //indexed from 1
			if (a == 0LL){
				return 1LL;
			}
			if (a == 1LL){
				return 1LL;
			}
			if (a == 2LL){
				return 1LL;
			}
			math::fibonacci::mat.clear();
			math::fibonacci::mat.assign(2, vector<long long int>(2, 0));
			math::fibonacci::mat[1][0] = 1LL;
			math::fibonacci::mat[0][1] = 1LL;
			math::fibonacci::mat[1][1] = 1LL;
			math::fibonacci::mat = math::matrix::ppow(mat, a - 2LL);
			long long int r = math::fibonacci::mat[0][1];
			r += mat[1][1];
			r %= MOD;
			return r;
		}
	}
	namespace factorial{
		vector<long long int> lo;
		vector<double> l2;
		void set_long(long long int b){
			if (lo.size()){
			}
			else{
				lo.push_back(1);
			}
			for (long long int i = lo.size(); i <= b; i++){
				lo.push_back(lo.back());
				lo.back() *= i;
				if (lo.back() >= MOD){
					lo.back() %= MOD;
				}
			}
		}
		void set_log(long long int b){
			if (l2.size()){
			}
			else{
				l2.push_back(log(0.0));
			}
			for (long long int i = l2.size(); i <= b; i++){
				l2.push_back(l2.back());
				l2.back() += log((double)(i));
			}
		}
		long long int get_long(int b){
			if (lo.size() <= b){
				set_long(b);
			}
			return lo[b];
		}
		double get_log(int b){
			if (l2.size() <= b){
				set_log(b);
			}
			return l2[b];
		}
	}
	namespace combination{
		long long int simpleC(long long int a, long long int b){
			if (a < b){
				return 0;
			}
			if (a - b < b){
				b = a - b;
			}
			long long int u = 1LL;
			for (long long int j = a; j >= a - b + 1LL; j--){
				u *= j;
				if (u >= MOD){
					u %= MOD;
				}
			}
			long long int s = 1LL;
			for (long long int i = 1LL; i <= b; i++){
				s *= i;
				if (s >= MOD){
					s %= MOD;
				}
			}
			return (u*ppow(s, MOD - 2)) % MOD;
		}
		long long int C(long long int a, long long int b){
			if (a < b){
				return 0;
			}
			long long int u = math::factorial::get_long(a);
			long long int s = math::factorial::get_long(b)*math::factorial::get_long(a - b);
			u %= MOD;
			s %= MOD;
			return (u*ppow(s, MOD - 2)) % MOD;
		}
		double logC(int a, int b){
			double u = math::factorial::get_log(a);
			double s = math::factorial::get_log(b) + math::factorial::get_log(a - b);
			return u - s;
		}
		long long int H(long long int a, long long int b){
			return math::combination::C(a + b - 1LL, b);
		}
		long long int simpleH(long long int a, long long int b){
			return math::combination::simpleC(a + b - 1LL, b);
		}
	}
	namespace prime{
		vector<long long int> prime;
		vector<long long int> use;  //smallest divisor
		void init(int b){
			use.assign(b + 1, 0);
			prime.clear();
			prime.push_back(2);
			use[2] = 2;
			for (int i = 3; i < use.size(); i += 2){
				if (use[i] == 0LL){
					prime.push_back(i);
					use[i] = i;
					for (int j = i * 2; j < use.size(); j += i){
						use[j] = i;
					}
				}
			}
		}
		vector<int> factorizetion(long long int num){
			vector<int> r;
			r.clear();
			for (int i = 0; i<prime.size() && prime[i] * prime[i] <= num; i++){
				while (num%prime[i] == 0LL){
					r.push_back(prime[i]);
					num /= prime[i];
				}
			}
			if (num > 1LL){
				r.push_back(num);
			}
			return r;
		}
		int size_of_factorization(long long int num){
			int cnt = 0;
			for (int i = 0; i<prime.size() && prime[i] * prime[i] <= num; i++){
				while (num%prime[i] == 0LL){
					cnt++;
					num /= prime[i];
				}
			}
			if (num > 1LL){
				cnt++;
			}
			return cnt;
		}
		long long int number_of_div(long long int num){
			long long int way = 1LL;
			long long int cnt = 0;
			for (int i = 0; i < prime.size() && prime[i] * prime[i] <= num; i++){
				cnt = 0;
				while (num%prime[i] == 0){
					cnt++;
					num /= prime[i];
				}
				way *= (cnt + 1LL);
			}
			if (num > 1LL){
				way *= 2LL;
			}
			return way;
		}
		bool isprime(int b){
			return binary_search(prime.begin(), prime.end(), b);
		}
		bool bruteprime(long long int b){
			for (long long int i = 2; i*i <= b; i++){
				if (b%i == 0LL){
					return true;
				}
			}
			return false;
		}
	}
}
using namespace math;
struct st{
	long long int u;
	long long int s;
	st(long long int u_ = 0,long long int s_=0){
		u = u_;
		s = s_;
	}
};
void y(st &a){
	long long int g = gcd(a.s, a.u);
	a.s /= g;
	a.u /= g;
}
st mul(st a, st b){
	st s;
	s.s = a.s*b.s;
	s.u = a.u*b.u;
	y(s);
	return s;
}
st div(st a, st b){
	swap(b.s, b.u);
	return mul(a, b);
}
st pluss(st a, st b){
	long long int k = lcm(a.s, b.s);
	a.u *= k / a.s;
	b.u *= k / b.s;
	a.s = b.s = k;
	a.u += b.u;
	y(a);
	return a;
}
vector<long long int> v;
vector<st> vv;
st A(st a,st b){
	st k2 = st(1, 1);
	st p = pluss(a, b);
	p = div(st(1, 1), p);
	y(p);
	return p;
}

int main(){
	for (int i = 0; i < 3; i++){
		int a;
		scanf("%d", &a);
		v.push_back(a);
	}
	sort(v.begin(), v.end());
	st k = st(v[0] * v[1] * (v[1] + v[2]), (v[2] + v[1])*(v[0] + v[1]));
	st kk = st(v[2] * v[1] * (v[1] + v[0]), (v[2] + v[1])*(v[0] + v[1]));
	long long int B = lcm(k.u, kk.u);
	k.u = B;
	y(k);
	printf("%lld/%lld\n", k.u, k.s);
	return 0;
}