import std.conv;
import std.stdio;
import std.string;
import std.numeric;
import std.algorithm;
import std.array;

void main() {
    int[] t; foreach (_; 0..3) { t ~= to!int(readln.strip); }

    int lcm = lcm(lcm(t[0], t[1]), t[2]);
    int[] nr = t.map!(ti => lcm / ti).array;
    int q = gcd(nr[0] - nr[2], nr[1] - nr[2]);
    int g = gcd(lcm, q);

    writef("%s/%s\n", lcm/g, q/g);
}

int lcm(int a, int b) {
    int g = gcd(a, b);
    int na = a / g;
    int nb = b / g;
    return na * nb * g;
}