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?
The first line contains a single integer t (1 \le t \le 1000)- the number of test cases.
Each of the next t lines contains four integers x, y, p and q (0 \le x \le y \le 109; 0 \le p \le q \le 109; y \gt 0; q \gt 0).
It is guaranteed that p/q is an irreducible fraction.
Hacks. For hacks, an additional constraint of t \le 5 must be met.
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.
4 3 10 1 2 7 14 3 8 20 70 2 7 5 6 1 1\n · · · \n · · · \n · · · \n · · · \n
4 10 0 -1\n \n \n \n
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.