js基础练习（一）

╰半橙微兮° 2023-02-11 08:53 9阅读 0赞

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <script>
            /**
             * 转十进制
             * @param str 进制字符串
             * @param n 目标进制
             * @returns {number}
             */
            function string2Algorism(str, n) {
                var charCode0 = "0".charCodeAt(),
                    charCode9 = "9".charCodeAt(),
                    result = 0;
                str = str.toUpperCase();
                for (var i = 0; i < str.length; i++) {
                    var c = str.charCodeAt(i);
                    var num = 0;
                    if (c >= charCode0 && c <= charCode9) {
                         num = Number(str.charAt(i));
                    } else {
                        num =c -55;
                    }
                    result+= Math.pow(n,str.length-i-1)*num;
                }
                return result;
            }
            /**
             * 十进制转任意进制
             * @param num
             * @param n
             * @returns {string}
             */
            function algorism2String(num,n) {
                var chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
                var result = "";
                while (num > 0) {
                    result = chars.charAt(num % n) + result;
                    num = parseInt(num / n);
                }
                return result;
            }
    
            /**
             * 十六进制转字符串
             * @param hexCharCodeStr
             * @returns {*}
             */
            function hexCharCodeToStr(hexCharCodeStr) {
                var trimedStr = hexCharCodeStr.trim();
                var rawStr =
                    trimedStr.substr(0,2).toLowerCase() === "0x"
                        ?
                        trimedStr.substr(2)
                        :
                        trimedStr;
                var len = rawStr.length;
                if(len % 2 !== 0) {
                    alert("Illegal Format ASCII Code!");
                    return "";
                }
                var curCharCode;
                var resultStr = [];
                for(var i = 0; i < len;i = i + 2) {
                    curCharCode = parseInt(rawStr.substr(i, 2), 16); // ASCII Code Value
                    resultStr.push(String.fromCharCode(curCharCode));
                }
                return resultStr.join("");
            }
            /**
             * 字符串转十六进制
             * @param str
             * @returns {*}
             */
            function strToHexCharCode(str) {
                if(str === "")
                    return "";
                var hexCharCode = [];
                hexCharCode.push("0x");
                for(var i = 0; i < str.length; i++) {
                    hexCharCode.push((str.charCodeAt(i)).toString(16));
                }
                return hexCharCode.join("");
            }
            /**
             * happynumber
             * @param num
             * @param results
             * @returns {boolean}
             */
            function isHappyNumber(num, results) {
                var nums = new Array(num.length).fill("").map(function (_, i) {
                    return parseInt(num.charAt(i))
                });
                nums.unshift(0);
                var result = (nums.reduce(function (total, p2) {
                    return total + p2 * p2;
                }));
                if (results.includes(result))return false;
                results.push(result);
                return result === 1 ? true : isHappyNumber("" + result, results);
            }
            for (var i = 0; i <= 1000; i++) {
                if(isHappyNumber(""+i,[])){
                    document.write(i+" ")
                }
            }
            /**
             * 冒泡排序
             * @param nums
             */
            function bubbleSort(nums) {
                for (var i = 0; i < nums.length-1; i++) {
                    for (var j = 0; j < nums.length-i-1; j++) {
                       if(nums[j]>nums[j+1]){
                           var temp=nums[j];
                           nums[j]=nums[j+1];
                           nums[j+1]=temp;
                       }
                    }
                }
                console.log(nums);
            }
            /**
             * 交换排序
             * @param nums
             */
            function exchangeSort(nums) {
                for (var i = 0; i < nums.length-1; i++) {
                    for (var j = i+1; j < nums.length; j++) {
                        if(nums[i]>nums[j]){
                            var temp=nums[i];
                            nums[i]=nums[j];
                            nums[j]=temp;
                        }
                    }
                }
                console.log(nums);
            }
            /**
             * 选择排序
             * @param nums
             */
            function selectSort(nums) {
                for (var i = 0; i < nums.length-1; i++) {
                    var selected=i;
                    for (var j = i+1; j < nums.length; j++) {
                       if(nums[j]<nums[selected]){
                           selected=j;
                       }
                    }
                    if(selected!==i){
                        var temp=nums[i];
                        nums[i]=nums[selected]
                        nums[selected]=temp;
                    }
                }
                console.log(nums);
            }
    //        console.log(isHappyNumber("19"))
        </script>
    </body>
    </html>