一、9×9乘法守则
[root@localhost opt]
c=0
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a;b++))
do
c=$[$a*$b]
echo -ne "$a*$b=$c\t"
done
echo ""
done
[root@localhost opt]
1*1=1
2*1=2 2*2=4
3*1=3 3*2=6 3*3=9
4*1=4 4*2=8 4*3=12 4*4=16
5*1=5 5*2=10 5*3=15 5*4=20 5*5=25
6*1=6 6*2=12 6*3=18 6*4=24 6*5=30 6*6=36
7*1=7 7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49
8*1=8 8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64
9*1=9 9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81
二、正直角三角形
方法一
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a;b++))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*
**
***
****
*****
******
*******
********
*********
方法二
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a-1;b++))
do
echo -n "*"
done
echo "*"
done
三、倒直角三角形
方法一
#!/bin/bash
for ((a=1;a<=9;a++))
do
for ((b=9;b>=$a;b--))
do
echo -n "*"
done
echo ""
done
方法二
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=9;b>=$a+1;b--))
do
echo -n "*"
done
echo "*"
done
[root@localhost opt]
*********
********
*******
******
*****
****
***
**
*
四、反方向的直角三角形
正的
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=9;b>=$a;b--))
do
echo -n " "
done
for ((c=1;c<=$a;c++))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*
**
***
****
*****
******
*******
********
*********
反的
#!/bin/bash
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a;b++))
do
echo -n " "
done
for ((c=9;c>=$a;c--))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*********
********
*******
******
*****
****
***
**
*
延伸:平行四边形
[root@localhost opt]
for ((a=1; a<=9; a++))
do
for ((b=9; b>=$a; b--))
do
echo -n " "
done
for ((c=1; c<=$a; c++))
do
echo -n "*"
done
for ((d=9;d>=$a;d--))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
**********
**********
**********
**********
**********
**********
**********
**********
**********
五、等腰三角形
正
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=9;b>=$a;b--))
do
echo -n " "
done
for ((c=1;c<=$a;c++))
do
echo -n "*"
done
for ((d=2;d<=$a;d++))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*
***
*****
*******
*********
***********
*************
***************
*****************
反
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a;b++))
do
echo -n " "
done
for ((c=9;c>=$a;c--))
do
echo -n "*"
done
for ((d=8;d>=$a;d--))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*****************
***************
*************
***********
*********
*******
*****
***
*
六、正梯形
正
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=9;b++))
do
echo -n "*"
done
for ((c=2;c<=$a;c++))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*********
**********
***********
************
*************
**************
***************
****************
*****************
反
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=9;b++))
do
echo -n "*"
done
for ((c=8;c>=$a;c--))
do
echo -n "*"
done
echo ""
done
七、等腰梯形
正
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=9;b>=$a;b--))
do
echo -n " "
done
for ((c=1;c<=$a;c++))
do
echo -n "*"
done
for ((d=2;d<=$a;d++))
do
echo -n "*"
done
for ((e=1;e<=9;e++))
do
echo -n "*"
done
echo ""
[root@localhost opt]
**********
************
**************
****************
******************
********************
**********************
************************
**************************
反
[root@localhost opt]
for ((a=1;a<=9;a++))
do
for ((b=1;b<=$a;b++))
do
echo -n " "
done
for ((c=9;c>=$a;c--))
do
echo -n "*"
done
for ((d=10;d>=$a;d--))
do
echo -n "*"
done
for ((e=1;e<=9;e++))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
****************************
**************************
************************
**********************
********************
******************
****************
**************
************
八、菱形
[root@localhost opt]
for ((a=1; a<=9; a++))
do
for ((b=9; b>=$a; b--))
do
echo -n " "
done
i=$[($a*2)-1]
for ((c=1; c<=$i; c++))
do
echo -n "*"
done
echo ""
done
for ((a=1;a<=9;a++))
do
for ((b=0; b<=$a; b++ ))
do
echo -n " "
done
for ((c=8;c>=$a;c--))
do
echo -n "*"
done
for (( d=7; d>=$a; d-- ))
do
echo -n "*"
done
echo ""
done
[root@localhost opt]
*
***
*****
*******
*********
***********
*************
***************
*****************
***************
*************
***********
*********
*******
*****
***
*