Write a function that calculates the cumulative sum of all integers from 1 up to a given positive integer n using a for loop.

• Define a function named cumulativeSum that takes an integer n as its parameter;
• Use a for loop to add all numbers from 1 to n and store the result;
• Return the final sum from the function;
• Do not use any library functions for summation; implement the logic using a for loop only.