Algorithmic Number XMay 13, 2025https://oi-wiki.org/math/number-theory/quad-residue/ https://zx31415.wordpress.com/2012/05/02/%e7%ae%97%e6%b3%95%e6%95%b0%e8%ae%ba%e4%b8%ad%e7%9a%84%e6%a4%ad%e5%9c%86%e6%9b%b2%e7%ba%bf/ https://zx31415.wordpress.com/2012/08/05/%E4%BB%A3%E6%95%B0%E6%95%B0%E8%AE%BA%EF%BC%9A%E5%88%86%E6%AD%A7%E7%90%86%E8%AE%BA/