九九乘法表

for循环
for ((i=1;i<=9;i++))
do
for ((j=1;j<=i;j++))
do
let c=$i*$j
echo -n " $i*$j=$c "
done
echo
done
echo "end!"



2.while循环
i=1;
j=1;
while((i<=9))
do
while((j<=i))
do
let "temp=i*j"
echo -ne "$i*$j=$temp\t"
done
let i++
let j=1
echo ""
done


3.until循环
i=1
until ((i>9))
do
let j=1
until ((j>i))
do
let "temp=i*j"
echo -ne "$i*$j=$temp\t"
let j++
done
let i++
echo ""
done