sqrtx/

Author: masx200

README.md

@@ -36,6 +36,10 @@ https://leetcode-cn.com/problems/unique-morse-code-words/
 
 https://leetcode-cn.com/problems/shu-zhi-de-zheng-shu-ci-fang-lcof/
 
+https://leetcode-cn.com/problems/sqrtx/
+
+https://leetcode-cn.com/problems/jJ0w9p/
+
 #### 安装教程
 
 1. 安装`deno`

jJ0w9p/index.ts

@@ -0,0 +1 @@
+export { default } from "../sqrtx/index.ts";

mod.ts

@@ -30,3 +30,5 @@ export { default as que_shi_de_shu_zi_lcof } from "./que-shi-de-shu-zi-lcof/inde
 export { default as find_all_numbers_disappeared_in_an_array } from "./find-all-numbers-disappeared-in-an-array/index.ts";
 export { default as move_zeros } from "./move-zeroes/index.ts";
 export { default as unique_morse_code_words } from "./unique-morse-code-words/index.ts";
+export { default as sqrt_x, SqrtNumber } from "./sqrtx/index.ts";
+export { default as jJ0w9p } from "./jJ0w9p/index.ts";

sqrtx/index.ts

@@ -0,0 +1,33 @@
+export default function mySqrt(x: number): number {
+    if (x < 0) {
+        throw Error("should greater than 0:" + x);
+    }
+    if (x === 0) {
+        return 0;
+    }
+    if (x === 1) {
+        return 1;
+    }
+    const delta = 1e-1;
+    const y = SqrtNumber(x, delta);
+    return Math.floor(Math.abs(y));
+}
+export function SqrtNumber(x: number, delta: number = Number.EPSILON): number {
+    if (x < 0) {
+        throw Error("should greater than 0:" + x);
+    }
+    if (x === 0) {
+        return 0;
+    }
+    if (x === 1) {
+        return 1;
+    }
+    // const delta = 1e-1;
+    let y = x;
+    let z = x;
+    while (z == x || Math.abs(z - y) > delta) {
+        z = y;
+        y = (x + y * y) / 2 / y;
+    }
+    return Math.abs(y);
+}

sqrtx/test.ts

@@ -0,0 +1,59 @@
+import { assertAlmostEquals, assertEquals } from "../deps.ts";
+import { sqrt_x, SqrtNumber } from "../mod.ts";
+Deno.test("sqrt-x", () => {
+    const examples: {
+        input: Parameters<typeof sqrt_x>[0];
+        output: ReturnType<typeof sqrt_x>;
+    }[] = [
+        { input: 0, output: 0 },
+        { input: 1, output: 1 },
+        { input: 4, output: 2 },
+        { input: 8, output: 2 },
+        { input: 9, output: 3 },
+        { input: 2, output: 1 },
+        { input: 3, output: 1 },
+        { input: 5, output: 2 },
+        { input: 6, output: 2 },
+        { input: 7, output: 2 },
+        { input: 10, output: 3 },
+        { input: 11, output: 3 },
+        { input: 12, output: 3 },
+        { input: 13, output: 3 },
+        { input: 14, output: 3 },
+        { input: 15, output: 3 },
+        { input: 16, output: 4 },
+        { input: 17, output: 4 },
+    ];
+    examples.forEach(({ input, output }) => {
+        assertEquals(output, sqrt_x(input));
+    });
+});
+
+Deno.test("SqrtNumber", () => {
+    const examples: {
+        input: Parameters<typeof SqrtNumber>[0];
+        output: ReturnType<typeof SqrtNumber>;
+    }[] = [
+        { input: 0, output: 0 },
+        { input: 1, output: 1 },
+        { input: 4, output: 2 },
+        { input: 8, output: 2.8284271247461903 },
+        { input: 9, output: 3 },
+        { input: 2, output: 1.4142135623730951 },
+        { input: 3, output: 1.7320508075688772 },
+        { input: 5, output: 2.23606797749979 },
+        { input: 6, output: 2.449489742783178 },
+        { input: 7, output: 2.6457513110645907 },
+        { input: 10, output: 3.1622776601683795 },
+        { input: 11, output: 3.3166247903554 },
+        { input: 12, output: 3.4641016151377544 },
+        { input: 13, output: 3.605551275463989 },
+        { input: 14, output: 3.7416573867739413 },
+        { input: 15, output: 3.872983346207417 },
+        { input: 16, output: 4 },
+        { input: 17, output: 4.123105625617661 },
+    ];
+    examples.forEach(({ input, output }) => {
+        assertAlmostEquals(output, SqrtNumber(input, 1e-10));
+    });
+});