How to find the sum of numbers in the range from 1 to n (n is entered by the user), step 1?

Question

C++ / C#

How to find the sum of numbers between 1 and n(user input), step 1, through a loop?
Entered for example 5, displays
1
2
3
4
5
How can I calculate the sum of digits from 1 to n (roughly speaking).

Answer 1

Get a counter (variable) and in a cycle from 1 to n add one to the counter.
Or use the formula for calculating the sum for an arithmetic progression.