feat: add birthday paradox

README.md

@@ -8,4 +8,4 @@
 | Sqrt10                  | 求 $\sqrt{10}$【连分数】 | [resolve-sqrt-10](https://hatter.ink/static/resource/muboard/?id=resolve-sqrt-10&version=latest&full=1)                     |
 | WallisProduct           | 沃里斯乘积              | [wallis-product](https://hatter.ink/static/resource/muboard/?id=wallis-product&version=latest&full=1)                       |
 | EulerNumber             | 欧拉数                | [eulers-number](https://hatter.ink/static/resource/muboard/?id=eulers-number&version=latest&full=1)                         |
-
+| BirthdayParadox         | 生日悖论               | [birthday-paradox](https://hatter.ink/static/resource/muboard/?id=birthday-paradox&version=latest&full=1)                   |