shell脚本嵌套循环

Question

现在需要检测两个变量x,y。写了两个for循环，报错

Answer 1

按类似下面的写法写

for x in {1..3}
do
    for y in {4..6}
    do
        echo $x
        echo $y
    done
done

Answer 2

sh里不支持{1..3}这种写法，如果用bash运行就ok了

for x in `seq 1 3`
do
    for y in `seq 4 6`
    do
        echo $x
        echo $y
    done
done