#!/bin/sh

#bubbling arithmetic function bubbling(){  len=${#data[*]}  ((len=len-1))  pos=0  for ((i=0;i<${#data[*]};i++))  do    flag="0"  #using flag to end the foreach #   echo "${i} ${len}"    for ((j=0;j<${len};j++))    do #    echo "for to ij position ${flag} ${len}" #    echo "output data values ${data[$j]} ${data[$[j+1]]}"     if [ ${data[j]} -gt ${data[j+1]} ]     then #     echo "for to ${j} position ${flag} $[len-1]" #      data[0]=${data[$[j]]}      tmp=${data[j]}  #swap array data      data[$j]=${data[j+1]}      data[$[j+1]]=${tmp}      pos=$j      flag="1"     fi #    echo "sort data are:${data[*]}"     done    len=${pos} #   echo "len and pos values are ${len} ${pos}"    if [ ${flag} -eq "0"  ]    then      break    fi  done  echo ${data[*]}  #return 1 } data=(1 5 6 9 2 6) #array data bubbling ${data}  #invoking method and by value echo "${data[*]}"    #return values

注：“$”符号表示引用变量，其中${data[$[j+1]]}和${data[${j+1}]}是不一样的，${data[$[j+1]]}表示先让j+1作运算并获取下标值，而${data[${j+1}]}仅表示获取j的下标值，关于+1它会自动忽视掉，若有更优化的算法，可以一块分享，探讨