Answer:
The c++ program for the given scenario is as follows.
#include <iostream>
using namespace std;
int main() {
int k, total;
k=1;
total=0;
while(k<=50)
{
// square of every counting number is added to total
total = total + (k*k);
// value of k is incremented to move on to the next counting number
k++;
}
cout<<"Sum of squares of first 50 counting numbers is " << total<<endl;
return 0;
}
OUTPUT
Sum of squares of first 50 counting numbers is 42925
Explanation:
As mentioned, only two variables k and total are used in the program. These variables are declared with data type integer.
Variable k is initialized to 1 and variable total is initialized to 0.
k=1;
total=0;
Variable k is used to represent counting number whose square is added to the variable total. Hence, values are taken accordingly.
The while loop is also known as the pre-test loop. This loop first evaluates the given condition and executes if the condition is satisfied.
while(k<=50)
The above while loop will execute till the value of variable k is less than or equal to 50. Once the value of k exceeds 50, the loop gets terminated. The loop executes 50 times, beginning from the value of 1 till k reaches 50.
The value of k is squared and added to the variable total each time the loop executes.
total = total + (k*k);
After the square is added to total, value of variable k is incremented by 1. This new value represents the next counting number.
k++;
After 50 executions of the loop, total variable will hold the sum of the squares of all the numbers from 1 to 50. The sum is displayed at the end.
This program implements the simplest logic for calculation of sum using two variables. The other loops such as for loop and do-while loop only differ in the placement and/or evaluation of the test condition.
