js常见算法

Posted 2020-10-23 limengbo

1.每个单词手字母大写

var capitalizeEveryWord = str => str.replace(/\b[a-z]/g, char => char.toUpperCase());
capitalizeEveryWord(‘hello world‘);

2.计算平均数

var calculatedMean = arr => arr.reduce((total, number) => total + number, 0) / arr.length;
calculatedMean([1, 2, 3])

 3.驼峰命名

const camelCase = str => str.replace(/-(\w)/g, (char1, char2) => char2.toUpperCase());
console.log(camelCase(‘hello-world‘));

4.计算数字在数组中出现次数

const numberOfReplications = (arr, num) => arr.reduce((m, n) => num == n ? m+1 : m+0, 0);
numberOfReplications([1, 2, 3, 1], 1);

 5.解析URL参数

const getQueryString = (name) =>{
     const reg = new RegExp("(^|&)"+ name +"=([^&]*)(&|$)");
     const r = window.location.search.substr(1).match(reg);
     if(r) return  decodeURI(r[2]); 
    return null;
}

 6.求数组中最大值

const maximum = arr => Math.max(...arr);
maximum([1,2,10]);

7.求数组中最小值

const minimum = arr => Math.min(...arr);
 minimum([1,2,3,4]);

 请大家多多指出不足。。。