Iteration (Cambridge (CIE) O Level Computer Science): Revision Note

Count controlled

FOR X ← 1 TO 10
    OUTPUT "Hello"
NEXT X

for x in range(10):
    print("Hello")

This will print the word "Hello" 10 times

FOR X ← 2 TO 10 STEP 2
    OUTPUT X
NEXT X

for x in range(2,12,2):
    print(x)
# Python range function excludes end value

This will print the even numbers from 2 to 10 inclusive

FOR X ← 10 TO 0 STEP -1
    OUTPUT X
NEXT X

for x in range(10,-1,-1):
    print(x)
# Python range function excludes end value

This will print the numbers from 10 to 0 inclusive

Post-condition

REPEAT
    INPUT Colour
UNTIL Colour = "red"

# NOT USED IN PYTHON

REPEAT
    INPUT Guess
UNTIL Guess = 42

# NOT USED IN PYTHON

Pre-condition

WHILE Colour != "Red" DO
    INPUT Colour
ENDWHILE

while colour != "Red":
    colour = input("New colour")

INPUT Temperature
WHILE Temperature > 37 DO
    OUTPUT "Patient has a fever"
    INPUT temperature
ENDWHILE

temperature = float(input("Enter temperature: "))
while temperature > 37:
    print("Patient has a fever")
    temperature = float(input("Enter temperature: "))

Total ← 0 

FOR Row ← 1 TO MaxRow 
    RowTotal ← 0 

    FOR Column ← 1 TO 10 
        RowTotal ← RowTotal + Amount[Row, Column] 
    NEXT Column 

    OUTPUT "Total for Row ", Row, " is ", RowTotal 
    Total ← Total + RowTotal 

NEXT Row 

OUTPUT "The grand total is ", Total

# Program to print a multiplication table up to a given number

# Prompt the user to enter a number
number = int(input("Enter a number: "))

# Set the initial value of the counter for the outer loop
outer_counter = 1

# Outer loop to iterate through the multiplication table
while outer_counter <= number:
    # Set the initial value of the counter for the inner loop
    inner_counter = 1

    # Inner loop to print the multiplication table for the current number
    while inner_counter <= 10:
        # Calculate the product of the outer and inner counters
        product = outer_counter * inner_counter

        # Print the multiplication table entry
        print(outer_counter, "x", inner_counter, "=", product)

        # Increment the inner counter
        inner_counter = inner_counter + 1

    # Move to the next number in the multiplication table
    outer_counter = outer_counter + 1