Question

Python 3

A program will be written that outputs various geometric shapes, rendered in characters, line-by-line using nested loops.

Here is what you need to know:

1- Copy this and don't change the inputs in the provided code:

# Get the size and drawing character from the user
size = input('Please enter the size: ')

# Validate the input, exit if bad
if size.isdigit():
    size = int(size)
else:
    print("Exiting, you didn't enter a number:", size)
    exit(1)

# Input the drawing character
drawingChar = input('Please enter the drawing character: ')

# Output an empty line
print()

#===============================================================
# Draw a Square
row = 1
while row <= size:
    # Output a single row
    col = 1
    while col <= size:
        if col <= size:
            # Output the drawing character
            print(drawingChar, end=' ')

        # The next column number
        col = col + 1

    # Output a newline to end the row
    print()

    # The next row number
    row = row + 1
print()

#===============================================================
# Draw a Lower-Left Triangle

#===============================================================
# Draw a Diagonal

#===============================================================
# Draw an Upper-Right Triangle

#===============================================================
# Draw a Reverse Diagonal

#===============================================================
# Draw a Lower-Right Triangle

#===============================================================
# Draw a ...

2. Comments on the shapes:

• Square - Done, look at the code.
• Lower-left Triangle - Like the square but each row has a different length. The length of each row increases by 1 each row.
• Diagonal - Like the lower-left Triangle but output a space instead of the drawing character, then output a single drawing character after the spaces.
• Upper-right triangle - Like the diagonal but instead of outputting a single character output a decreasing number of the drawing character.
  Two inner loops will be necessary, one to output spaces followed by one to output the drawing character.
• Reverse Diagonal - The reverse of the previous diagonal, upper-right to lower-left.
• Lower-right triangle - Like the just previous diagonal but instead of outputting a single character output an increasing number of the drawing character.
  Two inner loops will be necessary, one to output spaces followed by one to output the drawing character.

3. Some sample outputs:

• Size 8, drawing character 'o'

Please enter the size: 8
Please enter the drawing character: o
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 
o o o o o o o o 

o 
o o 
o o o 
o o o o 
o o o o o 
o o o o o o 
o o o o o o o 
o o o o o o o o 

o
  o
    o
      o
        o
          o
            o
              o

o o o o o o o o 
  o o o o o o o 
    o o o o o o 
      o o o o o 
        o o o o 
          o o o 
            o o 
              o 

              o
            o
          o
        o
      o
    o
  o
o

              o 
            o o 
          o o o 
        o o o o 
      o o o o o 
    o o o o o o 
  o o o o o o o 
o o o o o o o o 

• Size 14, drawing character '+'

Please enter the size: 16
Please enter the drawing character: +
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 

+ 
+ + 
+ + + 
+ + + + 
+ + + + + 
+ + + + + + 
+ + + + + + + 
+ + + + + + + + 
+ + + + + + + + + 
+ + + + + + + + + + 
+ + + + + + + + + + + 
+ + + + + + + + + + + + 
+ + + + + + + + + + + + + 
+ + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 

+
  +
    +
      +
        +
          +
            +
              +
                +
                  +
                    +
                      +
                        +
                          +
                            +
                              +

+ + + + + + + + + + + + + + + + 
  + + + + + + + + + + + + + + + 
    + + + + + + + + + + + + + + 
      + + + + + + + + + + + + + 
        + + + + + + + + + + + + 
          + + + + + + + + + + + 
            + + + + + + + + + + 
              + + + + + + + + + 
                + + + + + + + + 
                  + + + + + + + 
                    + + + + + + 
                      + + + + + 
                        + + + + 
                          + + + 
                            + + 
                              + 

                              +
                            +
                          +
                        +
                      +
                    +
                  +
                +
              +
            +
          +
        +
      +
    +
  +
+

                              + 
                            + + 
                          + + + 
                        + + + + 
                      + + + + + 
                    + + + + + + 
                  + + + + + + + 
                + + + + + + + + 
              + + + + + + + + + 
            + + + + + + + + + + 
          + + + + + + + + + + + 
        + + + + + + + + + + + + 
      + + + + + + + + + + + + + 
    + + + + + + + + + + + + + + 
  + + + + + + + + + + + + + + + 
+ + + + + + + + + + + + + + + + 

3. Outputting A Row Of characters: (how the code will look like)

- A row (line) of x's can be output with the following code:

# A string comprised of 1 character
drawingChar = 'x'

col = 1
while col <= size:
    # Output the drawing character
    print(drawingChar, end=' ')

    # The next column number
    col = col + 1

# Output a newline to end the row
print()

4. Outputting a rectangle of characters:

- If the above loop is done repeatedly, that is within another while loop, a square would be output.

# A string comprised of 1 character
drawingChar = 'x'

row = 1
while row <= size:

# Output a single row col = 1 while col <= size: # Output the drawing character print(drawingChar, end=' ') # The next column number col = col + 1

# Output a newline to end the row print() # The next row number row = row + 1 print()

We have a loop "within" a loop. This is called nested loops.

The first loop is called the outer loop and the loop "within" the outer loop is called the inner loop.

4. How to approach the problem?

There are two approaches you can use for drawing the shapes.

1. Use the condition of the inner while loop to control the output for each line.
   The experiments use this approach.
2. Run the inner while loop through the value of size and put an if statement in the inner loop to control the output for each line.

5. FINALLY, some additional notes to keep in mind for the shape program notes:

When the completed Shapes Program is run the following will happen:

1. A prompt and input for the size.
2. A prompt and input for a "drawing character".
   This character will be used to draw the shapes.
3. A square will be displayed.
4. A triangle will be displayed oriented to the "lower-left".
5. A diagonal will be displayed.
6. Another triangle will be displayed oriented to the "upper-right".
7. A reverse diagonal will be displayed.
8. A third triangle will be displayed oriented to the "lower-right".
9. An additional figure will be displayed.

See the sample output to see what each figure looks like.

Some possibilities for the additional figure:

• An isoceles triangle
• Some other triangle
• A trapeziod
• An X
• A diamond
• Something else of your own devising.

Disallowed additional figures:

• The additional figure can not be a single character.
• The additional figure can not be a vertical line.
• The additional figure can not be a horizontal line.
• The additional figure can not be a rectangle.

All figures must use nested loops, that is there will be a loop within a loop, as in the code above.

Do not use string concatenation or string methods.

Implement the shapes in the order above, one after the other in your program file.

Answer 1

# Get the size and drawing character from the user
size = input('Please enter the size: ')

# Validate the input, exit if bad
if size.isdigit():
    size = int(size)
else:
    print("Exiting, you didn't enter a number:", size)
    exit(1)

# Input the drawing character
drawingChar = input('Please enter the drawing character: ')

# Output an empty line
print()

#===============================================================
# Draw a Square
row = 1
while row <= size:
    # Output a single row
    col = 1
    while col <= size:
        if col <= size:
            # Output the drawing character
            print(drawingChar, end=' ')

        # The next column number
        col = col + 1

    # Output a newline to end the row
    print()

    # The next row number
    row = row + 1
print()

#===============================================================
# Draw a Lower-Left Triangle
row = 1
while row <= size:
    col = 1
    while col<=row:
        print(drawingChar ,end=' ')
        col = col + 1
    row = row + 1
    print()
print()
#===============================================================
# Draw a Diagonal
row = 1
while row <= size:
    col = 1
    while col<row:
        print(" ",end=' ')
        col = col+1
    print(drawingChar)
    row = row+1
print()
#===============================================================
# Draw an Upper-Right Triangle
# number of spaces
k = size - 1
for i in range(size, -1, -1):
    for j in range(k, 0, -1):
        print(end=" ")
    k = k + 1
    for j in range(0, i + 1):
        print(drawingChar, end=" ")
    print("")
print()
#===============================================================
# Draw a Reverse Diagonal
row = 1
s = size
while row <= size:
    col = 1
    while col<s:
        print(" ",end=' ')
        col = col+1
    s=s-1
    print(drawingChar)
    row = row+1
print()

#===============================================================
# Draw a Lower-Right Triangle
k = size - 1

# outer loop to handle number of rows
for i in range(0, size):

    # inner loop to handle number spaces
    # values changing acc. to requirement
    for j in range(0, k):
        print(end=" ")

        # decrementing k after each loop
    k = k - 1

    # inner loop to handle number of columns
    # values changing acc. to outer loop
    for j in range(0, i + 1):
        # printing stars
        print("{0} ".format(drawingChar), end="")

         # ending line after each row
    print("\r")