Question

I want to write a program to calculate Pi:Pi=4-4/3+4/5-4/7+4/9-4/11+...(the user inputs the number of terms in the series)

Answer 1

#include <iostream>

using namespace std;

double calc_PI(int termCount)
{
double result = 0.0;
double divider = 1;
char sign = 1;

while (termCount--)
{
result += (4 * sign / divider);
divider += 2;
sign = -sign;
}
return result;
}

int main()
{
int termCount;
cout << "Enter the number of series: ";
cin >> termCount;
cout << "PI = " << calc_PI(termCount);
return 0;
}