#include <iostream>
#include <cmath>
using namespace std;
double get_fmod(double a, double b) {
double f_mod = a;
if (a < 0)
f_mod = -a;
if (b < 0)
b = -b;
while (f_mod >= b)
f_mod = f_mod - b;
if (a < 0)
return -f_mod;
return f_mod;
}
int main()
{
double a = 10.7, b = 3.3;
cout << get_fmod(a, b) << endl;
cout << fmod(a, b);
return 0;
}
/*
run:
0.8
0.8
*/