如何在for循环中为可被3、5、同时被3和5整除的迭代值旁添加对应字符串

需求翻译 #

我需要写一个遍历1到15的for循环，实现如下逻辑：

• 所有可被3整除的数字旁打印"divisible by 3"
• 可被5整除的数字旁打印"divisible by 5"
• 同时可被3和5整除的数字旁打印"divisible by both"
• 其余数字直接打印即可

预期输出如下：

1
  2
  3 'divisible by 3'
  4
  5 'divisible by 5'
  6 'divisible by 3'
  7
  8
  9 'divisible by 3'
 10 'divisible by 5'
 11
 12 'divisible by 3'
 13
 14
 15 'divisible by both'

实现方案 #

核心注意点：必须优先判断是否同时被3和5整除，否则会先触发单整除条件，导致输出逻辑错误。

Python 实现代码

# range为左闭右开规则，要取到15需设置终止值为16
for num in range(1, 16):
    if num % 15 == 0:
        print(f"{num:2d} 'divisible by both'")
    elif num % 3 == 0:
        print(f"{num:2d} 'divisible by 3'")
    elif num % 5 == 0:
        print(f"{num:2d} 'divisible by 5'")
    else:
        print(f"{num:2d}")

JavaScript 实现代码

for (let num = 1; num <= 15; num++) {
    // 补空格对齐输出格式
    let output = num.toString().padStart(2, ' ');
    if (num % 15 === 0) {
        output += " 'divisible by both'";
    } else if (num % 3 === 0) {
        output += " 'divisible by 3'";
    } else if (num % 5 === 0) {
        output += " 'divisible by 5'";
    }
    console.log(output);
}

以上两种实现运行后的输出均和预期完全一致。

内容的提问来源于stack exchange，提问作者thinkerBOB