import java.io.*; public class Main {public static void main(String[] args) throws IOException {BufferedReader br = new BufferedReader(new InputStreamReader(System.in));}}

$$\displaystyle x^4 + ax^3 + bx^2 + cx + d = 0 \iff $$

$$\displaystyle x = -\frac{a}{4} \pm_s \frac{1}{2} \sqrt{\frac{a^2}{4} - \frac{2b}{3} + \frac{\sqrt[3]{2}(b^2 - 3ac + 12d)}{3\sqrt[3]{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}}} $$

$$\displaystyle \sqrt{... + \sqrt[3]{\frac{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}{54}}} $$

$$\displaystyle \pm_t \frac{1}{2} \sqrt{\frac{a^2}{2} - \frac{4b}{3} - \frac{\sqrt[3]{2}(b^2 - 3ac + 12d)}{3\sqrt[3]{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}}} $$

$$\displaystyle \sqrt{... - \sqrt[3]{\frac{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}{54}}} $$

$$\displaystyle \sqrt{... \pm_s \frac{-a^3 + 4ab -8c}{\frac{a^4}{4} - \frac{2b}{3} + \frac{\sqrt[3]{2}(b^2 - 3ac + 12d)}{3\sqrt[3]{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}} + \sqrt[3]{\frac{2b^3 - 9abc + 27c^2 + 27a^2d - 72bd + \sqrt{-4(b^2 - 3ac + 12d)^3 + (2b^3 - 9abc + 27c^2 + 27a^2d - 72bd)^2}}{54}}}} $$