同事发了一道shell题，是求一个多维数组中的最大和最小值
如文件 99file：
33 55 23 56 99
234 234 545 6546 34
11 43 534 33 75
43 34 76 756 33
343 890 77 667 55
我的实现之一：
#! /bin/bash echo "the file is :" cat 99shu max=0 min=999999 line=1 dnum=$(cat 99shu| wc -l) while (($line<=$dnum)) do for i in $(cat 99shu|head -"$line") do ((max<$i))&&max=$i ((min>$i))&&min=$i done let ++line done echo "the max number is: $max" echo "the min number is : $min"
结果：
the max number is: 6546
the min number is : 11
实现之二：
#! /bin/bash # echo the MAX and the MIN echo "the numbers is:" cat 99shu mnum=0 min=99999 while read line do declare -a arr=($line) lnum=$(echo $line | wc -w) i=0 while (( $i<$lnum )) do (($mnum<${arr[i]})) && mnum=${arr[i]} (($min>${arr[i]})) && min=${arr[i]} let ++i done done < 99shu echo "the max number is $mnum" echo "the min number is $min"
实现3，强大的awk
#! /bin/bash echo "the MAX number is: $( cat 99shu | awk '{for(i=1;i<=NF;i++)if(max<$i) max=$i;print max}'|tail -1)" echo "eht MIN number is: $( cat 99shu | awk '{min=999999;for(i=1;i<=NF;i++)if(min>$i)min=$i;print min}'|sort|head -1 )"
实现4：
#!/bin/bash min=$(cat 99shu | tr "t" "n"|tr " " "n"|sort -n|uniq|grep -v "^$"|head -1) max=$(cat 99shu | tr "t" "n"|tr " " "n"|sort -n|uniq|grep -v "^$"|tail -1) echo "The MAX number is $max" echo "The MIN number is $min"