要求:使用while循环编写脚本，使其完成以下功能：
1.提示用户输入两个整数:firstNum和secondNum(firstNum的值一定要小于secondNum)
2.输出所有介于这两数之间的奇数
3.输出所有介于这两数目之间偶数之和
先看一下如何用for循环实现:
#!/bin/bash
#chapter_8-14
echo "Please input two integer numbers(the first must be smaller than the second):"
read firstNum secondNum
#定义函数fun0，判断输入的两个数的大小
fun0()
{
while [ $1 -lt $2 ]
do
echo "Your input:" "$firstNum ""$secondNum"
break
done
}
fun0 $firstNum $secondNum
#定义一个数组，将两个数之间的所有数写入数组
declare -a arr1
i=firstNum
arr1=($(
for ((i=firstNum;i<=secondNum;i++))
do
echo -n "$i "
done
))
length=${#arr1[@]}
sum_even=0
if [[ "arr1[0]%2" -eq 0 ]]
then
for ((j=0;j<=length;j=j+2))
do
let sum_even+=arr1[j]
echo -n "${arr1[j+1]} "
done
echo "偶数之和为:" $sum_even
else
for ((k=0;k<=length;k=k+2))
do
let sum_even+=arr1[k+1]
echo -n "${arr1[k]} "
done
echo "偶数之和为:" "$sum_even "
fi
脚本执行效果:
[root@localhost charpter8]# sh 8-14 Please input two integer numbers(the first must be smaller than the second): 3 29 Your input: 3 29 3 5 7 9 11 13 15 17 19 21 23 25 27 29 偶数之和为: 208 [root@localhost charpter8]# sh 8-14 Please input two integer numbers(the first must be smaller than the second): 8 29 Your input: 8 29 9 11 13 15 17 19 21 23 25 27 29 偶数之和为: 198
while 循环实现:
#!/bin/bash
echo "Pleas input two integer number(the first num must be smaller than the second one):"
read firstNum secondNum
fun0()
{
while [ $1 -lt $2 ]
do
echo "Your input is:" "$firstNum " "$secondNum"
break
done
}
fun0 $firstNum $secondNum
declare -a arr1
let i=firstNum
arr1=(
$(
while ((i<=secondNum))
do
echo "$i "
let i++
done
)
)
length=${#arr1[@]}
j=0
k=0
sum_even=0
if [[ "arr1[0]%2" -eq 0 ]]
then
while ((j<length))
do
echo -n "${arr1[j+1]} "
let sum_even+=arr1[j]
let j=j+2
done
echo "偶数之和:$sum_even"
else
while ((k<length))
do
echo -n "${arr1[k]} "
let sum_even+=arr1[k+1]
let k=k+2
done
echo "偶数之和:$sum_even"
fi
脚本执行效果:
root@localhost charpter8]# sh 8-14-1 Pleas input two integer number(the first num must be smaller than the second one): 31 38 Your input is: 31 38 31 33 35 37 偶数之和:140 [root@localhost charpter8]# sh 8-14-1 Pleas input two integer number(the first num must be smaller than the second one): 30 39 Your input is: 30 39 31 33 35 37 39 偶数之和:170
两种循环实现发现大致相似.
