[code]

THe value for PI can be determined by the series equation

PI= 4x (1-1/3+1/5-1/7+1/9-1/11+1/13-...)

write a program to approximate the value of PI using the formula given including terms up through 1/99.

I wrote this code but not sure what I am doing wrong. please some one help.

thanks

Code:#include <stdio.h> #include <math.h> int main(void) { double x, y, z, sum, pi, i, n; sum = 1.0; for (i = 0, y = 3.0; i < n; ++i, y += 2.0) { z = 1.0 / y; if ((i & 1) == 0) sum -= z; else sum += z; } pi = 4.0 * sum; }