zoj3609 Modular Inverse（擴展歐幾裡德算法）

The modular modular multiplicative inverse of an integer a modulo m is an integer x such that a-1≡x (mod m). This is equivalent to ax≡1 (mod m).

Input

There are multiple test cases. The first line of input is an integer T ≈ 2000 indicating the number of test cases.

Each test case contains two integers 0 < a ≤ 1000 and 0 < m ≤ 1000.

Output

For each test case, output the smallest positive x. If such x doesn't exist, output Not Exist.

Sample Input

3
3 11
4 12
5 13

Sample Output

4
Not Exist
8

題意：已知a，m求最小的x滿足ax≡1（mod m）。

分析：擴展歐幾裡德的模板題，不多說。

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