vim 3sum.sh

#!/bin/bash

I=0

SUM=0

while [ $I -le 100 ];do

if [ $(($I % 3)) -eq 0 ];then

let SUM+=$I

fi

let I++

done

echo "The sum is $SUM"

实际上不管求几的倍数的和的方法都一样。下面写一下求所有五的倍数的和

vim 5sum.sh

#!/bin/bash

I=0

SUM=0

until  [ $I -gt 100 ];do

if [ $(($I % 5)) -eq 0 ];then

let SUM+=$I

fi

let I++

done

echo "The sum is $SUM"