shell程序输出数字塔

shell程序输出数字塔
如图所示：

#!/bin/bash

rows=4

for (( i=1; i<=rows; i++ ))
do
  for (( j=1; j<=i; j++ ))
  do
    echo -n "* "
  done
  echo
done
for (( i=1; i<=rows; i++ ))
do
  for (( j=1; j<=rows-i; j++ ))
  do
    echo -n "* "
  done
  echo
done
# 1 1
# 2 2
# 3 3
# 4 4
# 5 3
# 6 2
# 7 1

运行结果：

也可以输出正金子塔

程序如下：

#!/bin/bash

# echo "请输入金字塔的行数："
# read -r num

num=9

for ((i=1; i<=num; i++))
do
    for ((j=1; j<=num-i; j++))
        do
            echo -n " "
        done
  
    for ((k=1; k<=i; k++))
        do
            echo -n "$k "
        done
  
  echo
done