js实现乘法表

实现乘法表的方法

方法一：使用双重循环生成乘法表

for (let i = 1; i <= 9; i++) {
    let row = '';
    for (let j = 1; j <= i; j++) {
        row += `${j} x ${i} = ${i * j}\t`;
    }
    console.log(row);
}

方法二：使用数组和map方法生成乘法表

Array.from({ length: 9 }, (_, i) => i + 1).forEach(i => {
    const row = Array.from({ length: i }, (_, j) => j + 1)
        .map(j => `${j} x ${i} = ${i * j}`)
        .join('\t');
    console.log(row);
});

方法三：生成HTML格式的乘法表

function generateMultiplicationTable() {
    let table = '<table border="1">';
    for (let i = 1; i <= 9; i++) {
        table += '<tr>';
        for (let j = 1; j <= i; j++) {
            table += `<td>${j} x ${i} = ${i * j}</td>`;
        }
        table += '</tr>';
    }
    table += '</table>';
    document.body.innerHTML = table;
}
generateMultiplicationTable();

方法四：使用字符串模板生成乘法表

let table = '';
for (let i = 1; i <= 9; i++) {
    let row = '';
    for (let j = 1; j <= i; j++) {
        row += `${j}*${i}=${i * j} `;
    }
    table += `${row}\n`;
}
console.log(table);

方法五：递归实现乘法表

function printTable(i = 1, j = 1, row = '') {
    if (i > 9) return;
    if (j > i) {
        console.log(row);
        printTable(i + 1, 1, '');
        return;
    }
    row += `${j} x ${i} = ${i * j}\t`;
    printTable(i, j + 1, row);
}
printTable();