Description: You are an experienced Codeforces user. Today you found out that during your activity on Codeforces you have made y submissions, out of which x have been successful. Thus, your current success rate on Codeforces is equal to x / y. Your favorite rational number in the [0;1] range is p / q. Now you wonder: what is the smallest number of submissions you have to make if you want your success rate to be p / q? Input Format: The first line contains a single integer t (1 ≤ t ≤ 1000) — the number of test cases. Each of the next t lines contains four integers x, y, p and q (0 ≤ x ≤ y ≤ 109; 0 ≤ p ≤ q ≤ 109; y > 0; q > 0). It is guaranteed that p / q is an irreducible fraction. Hacks. For hacks, an additional constraint of t ≤ 5 must be met. Output Format: For each test case, output a single integer equal to the smallest number of submissions you have to make if you want your success rate to be equal to your favorite rational number, or -1 if this is impossible to achieve. Note: In the first example, you have to make 4 successful submissions. Your success rate will be equal to 7 / 14, or 1 / 2. In the second example, you have to make 2 successful and 8 unsuccessful submissions. Your success rate will be equal to 9 / 24, or 3 / 8. In the third example, there is no need to make any new submissions. Your success rate is already equal to 20 / 70, or 2 / 7. In the fourth example, the only unsuccessful submission breaks your hopes of having the success rate equal to 1.