編程題，任意語言都行，求幫助啊，題目在圖片裏

#include <iostream>

#include <cmath>

#include <iomanip>

using namespace std;

#define JIFEN_NUM 10000

double f(double x) {

if(x*x <=4) {

return (double)sqrt(4-x*x);

}

return 0.0;

}

double jifen(int num) {

double dx = 2.0/num;

double sum = 0.0;

for(int i=0; i<num; ++i) {

sum += f((i+1)*dx)*dx;

}

return sum;

}

int main()

{

cout<<"jifen="<<fixed<<setprecision(4)<<jifen(JIFEN_NUM)<<endl;

return 0;

}