Question

Write a function called sum_first_integers that takes a single positive integer parameter. The function should also return a positive integer. In particular, it should return the sum of the positive integers from 1 to the value passed into the function. For example, if 5 is passed into the function, it should return 15 because that is the number you get when you add 1 + 2 + 3 + 4 + 5. Hint: We recommend using the range function and a for loop.

Answer 1

To solve this problem, you can use a for loop and the range function to iterate from 1 to the given number and keep summing up the values.

Step-by-step explanation:

To solve this problem, you can use a for loop and the range function to iterate from 1 to the given number, and keep summing up the values. Here's an example:

def sum_first_integers(n):
total = 0
for i in range(1, n+1):
total += i
return total

# Example usage:
result = sum_first_integers(5)
print(result) # Output: 15

In this code, the variable 'total' is used to keep track of the running sum, initialized to 0. The for loop iterates from 1 to 'n+1', and at each iteration, the value of 'i' is added to 'total'. Finally, 'total' is returned as the result.

Answer 2

def sum_first_integers(n):

if n <= 0 or type(n) != int:

raise ValueError('Value must be a positive integer greater than 0')

total = 0

for num in range(1, n+1):

total += num

return total

Step-by-step explanation:

The above function was written in Python, the first if statement is for validation purposes and it ensures that the argument passed is a positive integer. If it is not, a ValueError is raised

We leveraged on Python's range function, which accepts three arguments although we passed in two arguments. The first argument is where the range function will start from and the second is where it will end. If we want the range function to stop at value n, then the argument has to be n+1(This is because machine starts counting numbers from 0) and the last argument is the step in which the increment is done. If no value is passed to this argument, Python assumes the value to be 1 which is what is done in this case.

Hence range(1, 5) = (1,2,3,4) and range (2, 10, 2) = 2,4,6,8