Sub-programs
A subprogram is a set of instructions that performs a specific task. It can be called (used) whenever needed in a program, which helps keep the code tidy and avoids repetition.
There are two main types:
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Procedures – do something, but don’t return a value.
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Functions – do something and return a value.
Why use sub-programs?
Why use subprograms?
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Makes code easier to read
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Avoids repeating the same code
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Makes testing easier
Subprograms are also called modules, functions, or procedures, depending on the language and context.
def add_nums():
num1 = int(input("Enter first number"))
num2 = int(input("Enter second number"))
total = num1 + num2
print("The total is", total)
# Main
add_nums()
def add_nums():
num1 = int(input("Enter first number"))
num2 = int(input("Enter second number"))
total = num1 + num2
return total
#Main
total = add_nums()
print("The total is", total)
Why return a value?
Returning a value is useful when you want to get a result from the subprogram and use it somewhere else in your program.
For example, you might want to return a total, a name, or a true/false answer.
Returning values helps:
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Share results between parts of the program
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Make the code more flexible and useful
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Avoid repeating calculations or tasks