Windy has *N* balls of distinct weights from 1 unit to *N* units. Now he tries to label them with 1 to *N* in such a way that:

- No two balls share the same label.
- The labeling satisfies several constrains like "The ball labeled with
*a*is lighter than the one labeled with*b".*

The first line of input is the number of test case. The first line of each test case contains two integers, *N* (1 ≤ *N* ≤ 200) and *M* (0 ≤ *M* ≤ 40,000). The next *M* line each contain two integers *a* and *b* indicating the ball labeled with *a* must be lighter than the one labeled with *b*. (1 ≤ *a, b* ≤ *N*) There is a blank line before each test case.

For each test case output on a single line the balls' weights from label 1 to label *N*. If several solutions exist, you should output the one with the smallest weight for label 1, then with the smallest weight for label 2, then with the smallest weight for label 3 and so on... If no solution exists, output -1 instead.

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