用for循环打印矩形，等腰三角形，菱形

1.打印出矩形

---

---

---

---

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#!/bin/bash

for ((i=0;i<5s;i++));do //控制行数
for ((j=0;j<5;j++));do //控制列数
echo -n "*" //打印
done
echo //换行
done
2.打印出等腰三角形

• • ---

  • ---

#!/bin/bash

for ((i=0;i<5;i++));do
for ((j=i+1;j<5;j++));do
echo -n " "
done
for ((k=0;k<=i;k++));do
echo -n "* "
done
echo
done
3.三角形

*
**

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* $o 4
$i = 5 3 $line-$i+1
** 6 2

• 7 1
  #!/bin/bash

read -p "input line:" line
o=$((($line+1)/2))
for((i=1;i<=$line;i++)); do
if [ $i -le $o ]; then
for ((j=1;j<=$i;j++)); do
echo -n ""
done
else
for ((k=1;k<=$(($line-$i+1));k++));do
echo -n ""
done
fi
echo
done