Sums

You are given two integers $L$ and $R$. Choose one or more distinct integers between $L$ and $R$, inclusive, and add the chosen integers.

Find the number of distinct sums that can be obtained.

The input is given in the following format:

$T$ $\mathrm{case}_1$ $\mathrm{case}_2$

For each test case, print the number of distinct sums modulo $10^9+7$.

• $1\leq T\leq200\,000$.
• $1\leq L\leq R\leq10^9$.