晕，得不了C的值。

[yuhongchun]

学习中遇到到个问题：

a=1
b=2
c=$a+$b
declare -i c
echo $c

本来想得到3的，却不料总得到1+2，晕了。。。唉，求正解。

[BigSnake.NET]

$((a+b))

[alinmn]

let c=$a+$b

[yuhongchun]

能用declare -i ; echo $c实现吗？

[yuhongchun]

我也用别的方法实现了，但想用declare的方式实现。。。

[BigSnake.NET]

先 declear -i c

[yuhongchun]

恩，我试试先，thank you very much.

[yuhongchun]

恩，确实，要先定义declare -i c，为什么呢???

[aBiNg]

代码： 全选

declare

Declare variables and give them attributes.

      -i   The variable is to be treated as an integer; 
           arithmetic evaluation is performed when the 
           variable is assigned a value.