JavaScript字典序比较

var strCode = function(s){
	let tokens = s.split('')
	if(tokens.length === 1){
		return ('z'.charCodeAt(0) - tokens[0].charCodeAt(0)) * (10 ** 0)
	}
	let result = 0
	for(let i = tokens.length - 1, j = 1; i > 0 ; i--,j++){
		result += ('z'.charCodeAt(0) - tokens[i].charCodeAt(0)) * (10 ** j)
	}
	return result;
}
function compareStrings_(s1, s2) {
	let tokens1 = s1.split('')
	let tokens2 = s2.split('')
	for(let i = 0; i < tokens1.length; i++){
		tokens1[i] = tokens1[i].charCodeAt(0)
	}
	for(let i = 0; i < tokens2.length; i++){
		tokens2[i] = tokens2[i].charCodeAt(0)
	}
	let result = 0;
	let minLen = -1;
	if(tokens1.length < tokens2.length){
		minLen = tokens1.length;
		result = -1
	}else if(tokens1.length > tokens2.length){
		minLen = tokens2.length;
		result = 1;
	}else {
		minLen = tokens1.length;
		result = 0;
	}
	//console.log(tokens1,tokens2,minLen,result)
	//双指针比较
	let pointer1 = 0
	let pointer2 = 0
	if(tokens1[0] > tokens2[0]){
		return 1
	}else if(tokens1[0] === tokens2[0]){

	}else{
		return -1;
	}
	while(tokens1[pointer1] === tokens2[pointer2]){
		pointer1++;
		pointer2++;
		if(tokens1[pointer1] > tokens2[pointer2]){
			result = 1
			break;
		}
		if(tokens1[pointer1] < tokens2[pointer2]){
			result = -1
			break;
		}
		if(pointer1 === minLen || pointer2 === minLen){
			break
		}
	}
	return result;
}
function compareStrings(s1, s2) {
    return s1.localeCompare(s2);
}

function randomString(length) {
    const chars = 'abcdefghijklmnopqrstuvwxyz';
    let result = '';
    for (let i = 0; i < length; i++) {
        result += chars[Math.floor(Math.random() * chars.length)];
    }
    return result;
}

function testCompareFunctions(iterations = 1000, maxStrLen = 10) {
    const progressBarLength = 50; // 进度条长度
    for (let i = 0; i < iterations; i++) {
        const len1 = Math.floor(Math.random() * maxStrLen) + 1; // 随机生成字符串长度
        const len2 = Math.floor(Math.random() * maxStrLen) + 1;
        const s1 = randomString(len1); // 随机生成第一个字符串
        const s2 = randomString(len2); // 随机生成第二个字符串

        const result1 = compareStrings_(s1, s2); // 用自定义的 compareStrings_ 函数
        const result2 = compareStrings(s1, s2);  // 用内置的 localeCompare 函数

        // 将 localeCompare 的结果标准化为 -1, 0, 1 以进行比较
        const normalizedResult2 = result2 === 0 ? 0 : (result2 > 0 ? 1 : -1);

        if (result1 !== normalizedResult2) {
            console.log(`Test failed for inputs: "${s1}" and "${s2}"`);
            console.log(`compareStrings_ result: ${result1}`);
            console.log(`localeCompare result: ${normalizedResult2}`);
            return; // 一旦发现不一致，停止测试并打印错误信息
        }

        // 进度条每隔一定的迭代次数更新
        if (i % Math.floor(iterations / 100) === 0 || i === iterations - 1) {
            const progress = (i / iterations) * 100; // 计算百分比
            const progressChars = Math.floor((progress / 100) * progressBarLength); // 进度条符号的数量
            const progressBar = '='.repeat(progressChars) + ' '.repeat(progressBarLength - progressChars); // 构建进度条
            process.stdout.write(`\r[${progressBar}] ${progress.toFixed(2)}%`); // \r 使光标回到行首，覆盖之前的输出
        }
    }
    console.log('\nAll tests passed!');
}

function testPerformance(iterations = 1000000, maxStrLen = 10) {
    const strings = [];

    // 预生成随机字符串对
    for (let i = 0; i < iterations; i++) {
        const len1 = Math.floor(Math.random() * maxStrLen) + 1;
        const len2 = Math.floor(Math.random() * maxStrLen) + 1;
        const s1 = randomString(len1);
        const s2 = randomString(len2);
        strings.push([s1, s2]);
    }

    // 测试自定义 compareStrings_ 的性能
    console.time('Custom compareStrings_');
    for (let i = 0; i < iterations; i++) {
        compareStrings_(strings[i][0], strings[i][1]);
    }
    console.timeEnd('Custom compareStrings_');

    // 测试内置 localeCompare 的性能
    console.time('Built-in localeCompare');
    for (let i = 0; i < iterations; i++) {
        strings[i][0].localeCompare(strings[i][1]);
    }
    console.timeEnd('Built-in localeCompare');
}

// 运行测试
testCompareFunctions(1000); // 这里设置较小的迭代次数，方便观察进度
// 运行性能测试
testPerformance(1000); // 设置 1000 次测试
//[================================================= ] 99.90%
//All tests passed!
//Custom compareStrings_: 0.395ms
//Built-in localeCompare: 0.158ms