#!/bin/bash

function sum()
{
    i=${#*}
    j=0
    m=0
    while [ $j -lt $i ]
    do
        ((m+=${arr[j]}))
        ((j++))
    done
    echo "数组和为$m"

}
read -a arr
sum ${arr[*]}                 

 #!/bin/bash
 function idnum()
 {
     uid=`id -u`
     gid=`id -g`
     echo $uid
     echo $gid     
 }
 
 ret=`idnum`
 echo $ret

思维导图