Answer:
The program to this question can be described as follows:
Program:
#include<iostream> //defining header file
#include<iomanip>
using namespace std;
int main() //defining main method
{
int n,i,div = 1; //defining integer variable
double PI = 0; //defining double variable
cout<< "Enter number of terms: "; //print message
cin >>n;//input number
while(n<1)//loop for input validation
{
cout << "Enter valid number of terms(atleast 1): "; //print message
cin >> n; //input value
}
for(i = 1; i <= n; i++) //loop to calcluate value
{
if(i % 2 == 0)//to check even number
PI =PI- (1.0/(div)); //hold value in PI
else//Odd iteration
PI =PI+ (1.0/(div)); //hold value in PI
div =div+ 2; //increment the value
}
PI =PI* 4;//Multiply summed values by 4
cout << "Approximation of PI = " << setprecision(10) << fixed << showpoint << PI; //print the value
return 0;
}
Output:
Enter number of terms: 8
Approximation of PI = 3.0170718171
Explanation:
In the above program code three integer variable "i,n and div", in which variable div assign a value that is 1, and a double variable PI is defined, that assign a value that is 0.
- The variable n is used to take input from the user end, that first checks input validation by using a while loop, and then the for loop is declared.
- Inside the for loop, it will use if statement, that checks even or odd number, in the even number it decrements the value PI, and in the odd number, it will calculate the total PI.
