linux 下shell加法操作总结：

#!/bin/bash

n=1;echo -n "$n "

let "n = $n + 1"

echo -n "$n "

: $((n = $n + 1))

echo -n "$n "

(( n = n +1 ))

echo -n "$n "

: $[ n = $n +1 ]

echo -n "$n "

n=$[ $n + 1 ]

echo -n "$n "

let "n++"

echo -n "$n "

(( n++ ))

echo -n "$n "

: $[ n++ ]

echo -n "$n "

echo

运行结果：1 2 3 4 5 6 7 8 9

图中红色高亮是比较容易接受的！我尽可能多的使用这两者！哈哈