<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> </head> <body> </body> </html> <script> //数组,冒泡排序,把数组从小到大排序 function bubbleSort(array) { if(Object.prototype.toString.call(array).slice(8, -1) === 'Array') { var len = array.length, temp; for(var i = 0; i < len - 1; i++) { for(var j = len - 1; j >= i; j--) { if(array[j] < array[j - 1]) { temp = array[j]; array[j] = array[j - 1]; array[j - 1] = temp; } } } return array; } else { return 'array is not an Array!'; } }; var arr = [23, 34, 3, 4, 23, 44, 333, 444]; console.log(bubbleSort(arr)); //数组,去重 function unique(arr) { var hash = []; for(var i = 0; i < arr.length; i++) { if(hash.indexOf(arr[i]) == -1) { hash.push(arr[i]); } } return hash; }; var arr2 = [2, 8, 5, 0, 5, 2, 6, 7, 2]; console.log(unique(arr2)); //数组,数组中出现最多的元素和最多元素的次数,第二多元素和第二多元素的次数 function aryMore(arr) { var i; var length = arr.length; var hash = []; //使用哈希数组 for(i = 0; i < length; i++) { if(!hash[arr[i]]) hash[arr[i]] = 1; //没有初始化的数组元素为undefined,undefined++为NaN else hash[arr[i]]++; } var max = 0; //最多的次数 var maxV; //出现最多的元素 var second = 0; //第二多的次数 var secondV; //出现第二多的元素 hash.forEach(function(item, index) { //forEach函数会跳过空元素 if(item > max) { second = max; secondV = maxV; max = item; maxV = index; //用索引来保存原数组的值 } else if(item > second) { second = item; secondV = index; } }); return { max, maxV, second, secondV }; } var arr3 = [2, 2, 2, 2, 3, 4, 5, 4, 3, 1, 4, 4, 100, 100]; console.log(aryMore(arr3)); //两个数组对比,取出不同的值 function getArrDifference(arr1, arr2) { return arr1.concat(arr2).filter(function(v, i, arr) { return arr.indexOf(v) === arr.lastIndexOf(v); }); }; var arr4 = [0, 1, 2, 3, 4, 5]; var arr6 = [0, 44, 6, 1, 3, 9]; console.log(getArrDifference(arr4, arr6)); //两个数组对比,取出相同的值 function getArrEqual(arr1, arr2) { let newArr = []; for(let i = 0; i < arr2.length; i++) { for(let j = 0; j < arr1.length; j++) { if(arr1[j] === arr2[i]) { newArr.push(arr1[j]); } } } return newArr; } var arr7 = [0, 1, 2, 3, 4, 5]; var arr8 = [0, 4, 6, 1, 33, 9]; console.log(getArrEqual(arr7, arr8)); //两个数组,把数组合并,去除相同的值 //合并两个数组,去重 function concatAry(arr1, arr2) { //不要直接使用var arr = arr1,这样arr只是arr1的一个引用,两者的修改会互相影响 var arr = arr1.concat(); //或者使用slice()复制,var arr = arr1.slice(0) for(var i = 0; i < arr2.length; i++) { arr.indexOf(arr2[i]) === -1 ? arr.push(arr2[i]) : 0; } return arr; }; var arr9 = [0, 1, 2, 3, 4, 5]; var arr10 = [0, 4, 6, 1, 3, 9]; console.log(concatAry(arr9, arr10)); //合并多个数组,去重 function concatAryMore(arr1, arr2, arr3) { if(arguments.length <= 1) { return false; } var concat_ = function(arr1, arr2) { var arr = arr1.concat(); for(var i = 0; i < arr2.length; i++) { arr.indexOf(arr2[i]) === -1 ? arr.push(arr2[i]) : 0; } return arr; } var result = concat_(arr1, arr2); for(var i = 2; i < arguments.length; i++) { result = concat_(result, arguments[i]); } return result; }; var arrMore1 = ['a', 'b']; var arrMore2 = ['a', 'c', 'd']; var arrMore3 = [1, 'd', undefined, true, null]; console.log(concatAryMore(arrMore1, arrMore2, arrMore3)); </script>