ARTS

ARTS

• A (Algotithm) 至少做一个leetcode的算法题
• R (Review) 阅读并点评一篇英文的技术文章
• T (Tip) 学习一个技术技巧
• S (Share) 分享一篇有观点和思考的技术文章

每周一次，坚持一年

Algorithm

Description ZigZag Conversion

Solution

/**
 * https://leetcode.com/problems/zigzag-conversion/
 * @param {string} s
 * @param {number} numRows
 * @return {string}
 */
var convert = function(s, numRows) {
    if (numRows == 1) return s;

    // let rows = new Array(numRows);
    var rows = [];
    for (var i = 0; i < numRows; i++) {
        rows[i] = [];
    }

    var curRow = 0;
    var goingDown = false;
    for (var i = 0; i < s.length; i++) {
        // if (!rows[curRow]) rows[curRow] = [];
        rows[curRow].push(s[i]);
        if (curRow === 0 || curRow === numRows - 1) goingDown = !goingDown;
        curRow += goingDown ? 1 : -1;
    }

    var result = '';
    for (var i = 0; i < rows.length; i++) {
        for (var j = 0; j < rows[i].length; j++) {
            result += rows[i][j];
        }
        // result += rows[i].join(''); // 原生的 for 循环更快。
        // result = result.concat(rows[i]); // concat 更慢。。。
    }
    return result;
};


console.log(convert('PAYPALISHIRING', 3), 'PAHNAPLSIIGYIR', convert('PAYPALISHIRING', 3) === 'PAHNAPLSIIGYIR');
console.log(convert('PAYPALISHIRING', 4), 'PINALSIGYAHRPI', convert('PAYPALISHIRING', 4) === 'PINALSIGYAHRPI');
console.log(convert('Apalindromeisaword,phrase,number,orothersequenceofunitsthatcanbereadthesamewayineitherdirection,withgeneralallowancesforadjustmentstopunctuationandworddividers.', 2)
    ===
    "Aaidoeswr,haenme,rtesqecouishtabrateaeaietedrcinwtgnrlloacsoajsmnsoucutoadodiiesplnrmiaodprs,ubroohreunefnttacneedhsmwynihrieto,iheeaalwnefrdutettpntainnwrdvdr."
)

// convert('PAYPALISHIRING', 3);

Review

Exploring EcmaScript Decorators https://medium.com/google-developers/exploring-es7-decorators-76ecb65fb841

探索 JS 装饰器

装饰器就是接收一个函数并返回具有附加功能的函数。装饰器为调用高阶函数提供了一种非常简单的语法。

Tip

bee’s knees

出類拔萃的人或事物

https://www.businessweekly.com.tw/article.aspx?id=18435&type=Blog

Share

未完待续…