C语言求π的值

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
void check_count();
void combineNum(int x, int y, int z,int num);
void printDiamond(int x, int y);
void purchaseChicken();
float calculatePi();
int main() {
    float pi = calculatePi();
    printf("pi值为%f\n",pi);
    return 0;
}

//计算pi值
float calculatePi() {
    float i = 1, j = 1, k = 2, pi = 1;
    while (i<=100000) {
        ++i;
        pi *= k / j;
        k = 2*i - k;
        j = 2*i - j;
         
        
    }
    return 2*pi;

}

计算公式π/2=2/1*2/3*4/3*4/5*6/5*........取10000项相乘

i值为3.141545
请按任意键继续. . .