Question

Write a function that takes an integer input n as a parameter and after it calculates the sum of 1+2+3+...+n, it returns the value to the main program. For example, if n=4, the output of the sum will be 10.

Answer 1

Source Code in C++:

#include <iostream> using namespace std; /*main function*/ int main() { /*function prototype*/ int calculateSum(int); /*variables*/ int n, sum; /*read integer n from the user*/ cout<<"Enter an integer n: "; cin>>n; /*function call*/ sum=calculateSum(n); /*print sum*/ cout<<"The sum is: "<<sum; return 0; }

/*function definition*/ int calculateSum(int n) { /*variables*/ int i, sum=0; /*using Loop to calculate sum*/ for(i=1;i<=n; i++) sum=sum+i; /*return sum*/ return sum; - }

Output:

C:\Users\Kumar Reddi\Desktop\trail.exe Enter an integer n: 4 The sum is: 10 Process exited after 0.7031 seconds with return value o Press any key to continue .

Code in text format (See above images of code for indentation):

#include <iostream>
using namespace std;
/*main function*/
int main()
{
   /*function prototype*/
   int calculateSum(int);
   /*variables*/
   int n,sum;
   /*read integer n from the user*/
   cout<<"Enter an integer n: ";
   cin>>n;
   /*function call*/
   sum=calculateSum(n);
   /*print sum*/
   cout<<"The sum is: "<<sum;
   return 0;
}
/*function definition*/
int calculateSum(int n)
{
   /*variables*/
   int i,sum=0;
   /*using loop to calculate sum*/
   for(i=1;i<=n;i++)
       sum=sum+i;
   /*return sum*/
   return sum;
}