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lint: remove class and main

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RiverTwilight 2023-01-02 20:49:35 +08:00
parent 6e2412f897
commit db2a91bd93
1 changed files with 137 additions and 143 deletions
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130
codes/javascript/chapter_computational_complexity/time_complexity.js
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@ -4,34 +4,33 @@
* Author: RiverTwilight (contact@rene.wang) * Author: RiverTwilight (contact@rene.wang)
*/ */
class time_complexity { /* 常数阶 */
/* 常数阶 */ function constant(n) {
constant(n) {
var count = 0; var count = 0;
const size = 100000; const size = 100000;
for (var i = 0; i < size; i++) count++; for (var i = 0; i < size; i++) count++;
return count; return count;
} }
/* 线性阶 */ /* 线性阶 */
linear(n) { function linear(n) {
var count = 0; var count = 0;
for (var i = 0; i < n; i++) count++; for (var i = 0; i < n; i++) count++;
return count; return count;
} }
/* 线性阶（遍历数组） */ /* 线性阶（遍历数组） */
arrayTraversal(nums) { function arrayTraversal(nums) {
var count = 0; var count = 0;
// 循环次数与数组长度成正比 // 循环次数与数组长度成正比
for (var i = 0; i < nums.length; i++) { for (var i = 0; i < nums.length; i++) {
count++; count++;
} }
return count; return count;
} }
/* 平方阶 */ /* 平方阶 */
quadratic(n) { function quadratic(n) {
var count = 0; var count = 0;
// 循环次数与数组长度成平方关系 // 循环次数与数组长度成平方关系
for (var i = 0; i < n; i++) { for (var i = 0; i < n; i++) {
@ -40,10 +39,10 @@ class time_complexity {
} }
} }
return count; return count;
} }
/* 平方阶（冒泡排序） */ /* 平方阶（冒泡排序） */
bubbleSort(nums) { function bubbleSort(nums) {
var count = 0; // 计数器 var count = 0; // 计数器
// 外循环：待排序元素数量为 n-1, n-2, ..., 1 // 外循环：待排序元素数量为 n-1, n-2, ..., 1
for (var i = nums.length - 1; i > 0; i--) { for (var i = nums.length - 1; i > 0; i--) {
@ -59,10 +58,10 @@ class time_complexity {
} }
} }
return count; return count;
} }
/* 指数阶（循环实现） */ /* 指数阶（循环实现） */
exponential(n) { function exponential(n) {
var count = 0, var count = 0,
base = 1; base = 1;
// cell 每轮一分为二，形成数列 1, 2, 4, 8, ..., 2^(n-1) // cell 每轮一分为二，形成数列 1, 2, 4, 8, ..., 2^(n-1)
@ -74,86 +73,81 @@ class time_complexity {
} }
// count = 1 + 2 + 4 + 8 + .. + 2^(n-1) = 2^n - 1 // count = 1 + 2 + 4 + 8 + .. + 2^(n-1) = 2^n - 1
return count; return count;
} }
/* 指数阶（递归实现） */ /* 指数阶（递归实现） */
expRecur(n) { function expRecur(n) {
if (n == 1) return 1; if (n == 1) return 1;
return this.expRecur(n - 1) + this.expRecur(n - 1) + 1; return expRecur(n - 1) + expRecur(n - 1) + 1;
} }
/* 对数阶（循环实现） */ /* 对数阶（循环实现） */
logarithmic(n) { function logarithmic(n) {
var count = 0; var count = 0;
while (n > 1) { while (n > 1) {
n = n / 2; n = n / 2;
count++; count++;
} }
return count; return count;
} }
/* 对数阶（递归实现） */ /* 对数阶（递归实现） */
logRecur(n) { function logRecur(n) {
if (n <= 1) return 0; if (n <= 1) return 0;
return this.logRecur(n / 2) + 1; return logRecur(n / 2) + 1;
} }
/* 线性对数阶 */ /* 线性对数阶 */
linearLogRecur(n) { function linearLogRecur(n) {
if (n <= 1) return 1; if (n <= 1) return 1;
var count = this.linearLogRecur(n / 2) + this.linearLogRecur(n / 2); var count = linearLogRecur(n / 2) + linearLogRecur(n / 2);
for (var i = 0; i < n; i++) { for (var i = 0; i < n; i++) {
count++; count++;
} }
return count; return count;
} }
/* 阶乘阶（递归实现） */ /* 阶乘阶（递归实现） */
factorialRecur(n) { function factorialRecur(n) {
if (n == 0) return 1; if (n == 0) return 1;
var count = 0; var count = 0;
// 从 1 个分裂出 n 个 // 从 1 个分裂出 n 个
for (var i = 0; i < n; i++) { for (var i = 0; i < n; i++) {
count += this.factorialRecur(n - 1); count += factorialRecur(n - 1);
} }
return count; return count;
}
} }
(function main() { var n = 8;
var test = new time_complexity(); console.log("输入数据大小 n = " + n);
var n = 8; var count = constant(n);
console.log("输入数据大小 n = " + n); console.log("常数阶的计算操作数量 = " + count);
var count = test.constant(n); count = linear(n);
console.log("常数阶的计算操作数量 = " + count); console.log("线性阶的计算操作数量 = " + count);
count = arrayTraversal(new Array(n));
console.log("线性阶（遍历数组）的计算操作数量 = " + count);
count = test.linear(n); count = quadratic(n);
console.log("线性阶的计算操作数量 = " + count); console.log("平方阶的计算操作数量 = " + count);
count = test.arrayTraversal(new Array(n)); var nums = new Array(n);
console.log("线性阶（遍历数组）的计算操作数量 = " + count); for (var i = 0; i < n; i++) nums[i] = n - i; // [n,n-1,...,2,1]
count = bubbleSort(nums);
console.log("平方阶（冒泡排序）的计算操作数量 = " + count);
count = test.quadratic(n); count = exponential(n);
console.log("平方阶的计算操作数量 = " + count); console.log("指数阶（循环实现）的计算操作数量 = " + count);
var nums = new Array(n); count = expRecur(n);
for (var i = 0; i < n; i++) nums[i] = n - i; // [n,n-1,...,2,1] console.log("指数阶（递归实现）的计算操作数量 = " + count);
count = test.bubbleSort(nums);
console.log("平方阶（冒泡排序）的计算操作数量 = " + count);
count = test.exponential(n); count = logarithmic(n);
console.log("指数阶（循环实现）的计算操作数量 = " + count); console.log("对数阶（循环实现）的计算操作数量 = " + count);
count = test.expRecur(n); count = logRecur(n);
console.log("指数阶（递归实现）的计算操作数量 = " + count); console.log("对数阶（递归实现）的计算操作数量 = " + count);
count = test.logarithmic(n); count = linearLogRecur(n);
console.log("对数阶（循环实现）的计算操作数量 = " + count); console.log("线性对数阶（递归实现）的计算操作数量 = " + count);
count = test.logRecur(n);
console.log("对数阶（递归实现）的计算操作数量 = " + count);
count = test.linearLogRecur(n); count = factorialRecur(n);
console.log("线性对数阶（递归实现）的计算操作数量 = " + count); console.log("阶乘阶（递归实现）的计算操作数量 = " + count);
count = test.factorialRecur(n);
console.log("阶乘阶（递归实现）的计算操作数量 = " + count);
})();