#include <iostream>
using namespace std;

long long modinv(long long a, long long m) {
    long long x = m, y = a, p = 1, q = 0, r = 0, s = 1;
    while (y != 0) {
        long long u = x / y;
        long long x0 = y; y = x - y * u; x = x0;
        long long r0 = p - r * u, s0 = q - s * u;
        p = r; r = r0; q = s; s = s0;
    }
    return q < 0 ? q + m : q;
}

long long CRT(long long a, long long x, int b, int y) {
    long long g = a, h = b;
    while (h > 0) { long long t = g; g = h; h = t % h; }
    if ((y - x) % g != 0) return -1;
    long long t = (y - x) / g % b * modinv(a/g, b/g) % b;
    long long ans = (x + a * t) % (a/g*b);
    if (ans < 0) ans += a/g*b;
    return ans;
}

long long lcm(long long a, long long b) {
    long long x = a, y = b;
    while (y > 0) { long long z = x; x = y; y = z % y; }
    return a / x * b;
}

int main() {
    int a, x, b, y, c, z; cin >> x >> a >> y >> b >> z >> c;
    long long ans = CRT(a, x, b, y);
    if (ans >= 0) ans = CRT(lcm(a, b), ans, c, z);
    cout << ans << endl;
}