循环语句的双重循环

循环语句的双重循环小例题

1.九九乘法表

#!/bin/bash
a=1
while [ $a -le 9 ]
  do
  b=1
 while [ $b -le $a ]
    do
     c=$[a * $b]
     echo -n -e "$a*$b=$c\t"

     let b++
 done
   let a++
      echo
done

2.一条直线

#!/bin/bash
for ((i=1; i<=10; i++))
do
 echo -n "*"
done

3.直角三角形

#!/bin/bash
for ((i=1; i<=9; i++))
  do

  for ((a=9; a>=$i; a--))
  do
   echo -n ""
 done

4.等腰三角形

#!/bin/bash
for ((i=1; i<=9; i++))
  do

  for ((a=9; a>=$i; a--))
  do
   echo -n " "
done
            
  for ((c=1; c<=$i; c++))
   do       
    echo -n "*" 
  done     
  
 for ((d=2; d<=$i; d++))
  do  
  echo -n "*"
done
    
echo ""
done 

5.倒等腰三角形

#!/bin/bash
for ((a=1; a<=10; a++))
do

  for ((b=1; b<=$a; b++))
  do
     echo -n " "
  done
  for ((c=10; c>=$a; c--))
  do
     echo -n "*" 
  done
  for ((d=9; d>=$a; d--))
  do
     echo -n "*"
  done

   echo ""
done

6.直角梯形

#!/bin/bash
for ((a=1; a<=9; a++))
do
   for ((b=9; b>=$a; b--))
   do
      echo -n " "
   done

   for ((c=1;c<=9+$a; c++))
   do
      echo -n "*"
   done
   echo ""
done

7.菱形

#!/bin/bash
for ((a=1; a<=9; a++))
do
  for ((b=10; b>=$a; b--))
  do
  echo -n " "
  done

  for ((c=1; c<=$a; c++))
  do
#!/bin/bash
for ((a=1; a<=9; a++))
do
  for ((b=10; b>=$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

for ((a=1; a<=10; a++))
do

  for ((b=1; b<=$a; b++))
  do
     echo -n " "
  done
  for ((c=10; c>=$a; c--))
  do
     echo -n "*" 
  done
  for ((d=9; d>=$a; d--))
  do
     echo -n "*"
  done

   echo ""
done

输入数字控制菱形的大小

#!/bin/bash
read -p "输入大小" i

for ((a=1;a<=$i;a++))
do
    for ((b=$i;b>=$a;b--))
    do
    echo -n " " 
    done
  for ((c=1;c<=$[$a*2-1];c++))
  do
  echo -n "*"
  done
 echo ""
done

for ((d=1;d<=$i+1;d++))
do
   for ((e=1;e<=$d-1;e++))
   do
   echo -n " "
   done
  for ((f=2*$i+1;f>=$[$d*2-1];f--))
  do
  echo -n "*"
  done
 echo ""
done