typedef long long L;
L gcd(L a,L b){
	for(;a^=b^=a^=b%=a;);
	return b;
}
L lcm(L a,L b){
	return a*b/gcd(a,b);
}

L a,b,c,l,x;
main(){
	scanf("%lld%lld%lld",&a,&b,&c);
	l=lcm(lcm(a,b),c);
	x=a=l/a,b=l/b,c=l/c;
	for(;--x,a%x!=b%x||b%x!=c%x;);
	printf("%lld/%lld\n",l,x);
	return 0;
}