企业shell编程基础问题解决实践-是骡子是马溜溜

第一题：
#!/bin/bash
read -p "Please Enter a number:" n
for ((x=1;x<=$n;x＋＋));do
  for ((y=1;y<=$n*2;y＋＋));do
  echo -n "＋"
  done
  echo
done
[root@Mysqlserver scripts]# sh b.sh
Please Enter a number:6
＋＋＋＋＋＋＋＋＋＋＋＋
＋＋＋＋＋＋＋＋＋＋＋＋
＋＋＋＋＋＋＋＋＋＋＋＋
＋＋＋＋＋＋＋＋＋＋＋＋
＋＋＋＋＋＋＋＋＋＋＋＋
＋＋＋＋＋＋＋＋＋＋＋＋
[root@Mysqlserver scripts]#
第二题：
#!/bin/bash
read -p "Please Enter a number:" n
for ((x=1;x<=$n;x＋＋));do
  for ((y=1;y<=$n;y＋＋));do
  echo -n "■"
  done
  echo
done
[root@Mysqlserver scripts]# sh d.sh
Please Enter a number:4
■■■■
■■■■
■■■■
■■■■
[root@Mysqlserver scripts]#
第三题：
#!/bin/bash
read -p "Please Enter a number:" n
for ((x=1;x<=$n;x＋＋));do
  for ((z=1;z<=$n-x;z＋＋));do
  echo -n " "
  done
  for ((y=1;y<=a＋1;y＋＋));do
  echo -n "*"
  done
  echo
  a=$((a＋2))
done
[root@Mysqlserver scripts]# sh e.sh
Please Enter a number:6
  *
  ***
  *****
*******
*********
***********
[root@Mysqlserver scripts]#
第四题：
#!/bin/bash
read -p "Please Enter a number:" n
for ((x=1;x<=$n;x＋＋));do
  for ((z=1;z<=x＋2;z＋＋));do
  echo -n "*"
  done
  echo
done
[root@Mysqlserver scripts]# sh h.sh
Please Enter a number:6
***
****
*****
******
*******
********