linux - 如何在 if else 语句的末尾修复此表达式？

Question

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Answer 1

用现代 bash 编写，可能如下所示:

#!/usr/bin/env bash
#              ^^^^- this uses bash-only syntax, so shebang must not be #!/bin/sh
#                    or script must be run as ''bash scriptname'', not ''sh scriptname''

read -p "Enter a number: " isdiv

if (( (isdiv % 15) == 0 )); then
    echo "$dvsbl is divisible by 15."
elif (( (isdiv % 5) == 0 && (isdiv % 15) != 0 )); then
    echo "$isdiv is divisible by 5 and not by 15."
elif (( (isdiv % 3) == 0 && (isdiv % 15) != 0 )); then
    echo "$isdiv is divisible by 3 and not by 15."
else
    nxtcls=$(( ( (isdiv / 15) + 1) * 15 ))
    echo "The next closest number to $isdiv that is divisible by 15 is $nxtcls"
fi

let 是 1970 年代的古老语法，不应在新代码中使用。 $(( )) 是 POSIX 指定的运行算术运算并替换其结果的方法。 (( )) 是一个 bash-only(因此，对于带有 #!/bin/bash shebang 的脚本，或者由具有相同扩展名的 shell 显式运行的脚本，例如ksh 或 zsh)