#include <bits/stdc++.h>
using namespace std;
const int N = 1e4 + 5;
const int mod = 1e9 + 7;
int main() {
  int n;
  int x, y, p, q;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d%d%d%d", &x, &y, &p, &q);
    if (!p && x || (p == q && x != y))
      puts("-1");
    else if (!p && !x || (p == q && x == y))
      puts("0");
    else {
      long long ans = max(ceil(x * 1.0 / p), ceil((y - x) * 1.0 / (q - p)));
      ans = ans * q - y;
      printf("%lld\n", ans);
    }
  }
  return 0;
}

### Prompt

Your task is to create a cpp solution to the following problem:

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

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

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.

Example

Input

4
3 10 1 2
7 14 3 8
20 70 2 7
5 6 1 1


Output

4
10
0
-1

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.

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
const int N = 1e4 + 5;
const int mod = 1e9 + 7;
int main() {
  int n;
  int x, y, p, q;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d%d%d%d", &x, &y, &p, &q);
    if (!p && x || (p == q && x != y))
      puts("-1");
    else if (!p && !x || (p == q && x == y))
      puts("0");
    else {
      long long ans = max(ceil(x * 1.0 / p), ceil((y - x) * 1.0 / (q - p)));
      ans = ans * q - y;
      printf("%lld\n", ans);
    }
  }
  return 0;
}

```