P2019 Four Squares Theorem
Description
For a positive integer $n$, find the number of ordered quadruples of integers $(a,b,c,d)$ such that $a^2+b^2+c^2+d^2=n$. The answer is taken modulo $10^9+7$.
Input Format
**This problem has multiple test cases**.
The first line contains an integer $T$, the number of test cases.
For each test case, one line contains a positive integer, representing the value of $n$.
Output Format
Output a total of $T$ lines.
On the $k$-th line, output a non-negative integer, which is the answer for the $k$-th test case modulo $10^9+7$.
Explanation/Hint
| Test point ID | Limit |
| :-----------: | :-----------: |
| $1\sim 3$ | $n\le 2\times 10^5$ |
| $4\sim 6$ | $n\le 10^{12}$ |
| $7\sim 10$ | None |
For all testdata, $1\le n\le 10^{18},1\le T\le 50$.
For the first test case of Sample 1, the following are all valid $(a,b,c,d)$ (not all feasible quadruples are listed here).
$$(1,1,1,1),(1,1,1,-1),(-1,-1,-1,-1),(2,0,0,0),(0,-2,0,0)$$
Translated by ChatGPT 5