Innome

Young software developer Michael succeeded on Innopolis Open and was awarded by Innobook laptop with a pre-installed "Innome" web browser. This strange web browser can support at most $k$ open windows and the $i$-th open tab in the window uses $i$ megabytes of memory. Michael knows that his new laptop has $m$ megabytes of memory. Please help Michael to calculate the maximum number of tabs he can open.

The first line contains single integer $t$, the number of tests. The next $t$ lines contains description of the tests one per line. Each test is represented by two integers $m$ and $k$,  the size of Innobook memory and the maximum possible number of windows.

For each test output a single integer on a separate line, the maximum number of tabs that Michael can open.