51 lines
1022 B
JavaScript
51 lines
1022 B
JavaScript
// 对数组进行复制，非引用赋值
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function copy(arr) {
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const arr2 = [];
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const len = arr.length;
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for (let i = 0; i < len; i++) {
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arr2[i] = arr[i];
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}
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return arr2;
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}
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// 关于sort排序
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// 数字排序方式，从小到大升序排列
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// sort函数接受的排序方法，返回的值应当为负数、0、正数，排序也按照这个顺序排序
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function sortNumber(a, b) {
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return a - b;
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}
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// 获取奇数
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function isOdd(num) {
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return num % 2 !== 0;
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}
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// 获取偶数
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function isEven(num) {
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return num % 2 === 0;
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}
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const nums = [];
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for (let i = 0; i < 20; i++) {
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nums[i] = i + 1;
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}
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const oddList = nums.filter(isOdd);
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const evenList = nums.filter(isEven);
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console.log(oddList);
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console.log(evenList);
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// 创建二维数组（表格）
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Array.matrix = function(numrows, numcols, initval) {
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const arr = [];
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for (let i = 0; i < numrows; i++) {
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const columns = [];
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for (let j = 0; j < numcols; j++) {
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columns[j] = initval;
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}
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arr[i] = columns;
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}
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return arr;
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} |