循環之-9*9乘法表

for循環變量的生策劃

1,for 變量 in 值1 值2 值3...  {1.2.4..5}>> 1 2 3 4 5

2,生成數字序列

    eq 1 5 > 1 2 3 4 5
    seq 1 3 10 >從1到10 步長是3

3，系統命令生成的序列

    for i in `ls -al /home`

4,自定義文件序列

新建一個文件list, 加入你須要循環的內容

for i in $(cat list)   或者 for i in `cat list`

 

[root@IBM shell]# cat 9_9.sh
#!/bin/bash
for((i=1;i<=9;i++))
do    
    for((j=1;j<=i;j++))
    do
        echo -n "$i * $j = $[ i * j ] "
        done
        echo #換行的做用也能夠用\t來代替

done

結果

[root@IBM shell]# ./9_9.sh 1 * 1 = 1 2 * 1 = 2 2 * 2 = 4 3 * 1 = 3 3 * 2 = 6 3 * 3 = 9 4 * 1 = 4 4 * 2 = 8 4 * 3 = 12 4 * 4 = 16 5 * 1 = 5 5 * 2 = 10 5 * 3 = 15 5 * 4 = 20 5 * 5 = 25 6 * 1 = 6 6 * 2 = 12 6 * 3 = 18 6 * 4 = 24 6 * 5 = 30 6 * 6 = 36 7 * 1 = 7 7 * 2 = 14 7 * 3 = 21 7 * 4 = 28 7 * 5 = 35 7 * 6 = 42 7 * 7 = 49 8 * 1 = 8 8 * 2 = 16 8 * 3 = 24 8 * 4 = 32 8 * 5 = 40 8 * 6 = 48 8 * 7 = 56 8 * 8 = 64 9 * 1 = 9 9 * 2 = 18 9 * 3 = 27 9 * 4 = 36 9 * 5 = 45 9 * 6 = 54 9 * 7 = 63 9 * 8 = 72 9 * 9 = 81