유리수의 사칙연산(Rational number Four fundamental rules of arithmetics)(add, subtraction, multiplication, division

유리수의 사칙연산(Rational number Four fundamental rules of arithmetics).cc

#include<iostream>

using namespace std;

typedef struct _Rational {
	int bunZa, bunMo;
} Rational;

//Greatest common divisior(최대공약수)
int GCD(int a, int b)
{
	if (b == 0) return a;
	else return GCD(b, a%b);
}

//Least common multiple(최소공배수)
int LCM(int a, int b)
{
	return a*b / GCD(a, b);
}

//Reduction(약분)
Rational reduction(Rational a)
{
	int gcd = GCD(a.bunZa, a.bunMo);
	a.bunZa /= gcd;
	a.bunMo /= gcd;
	return a;
}

//Add
Rational RationalAdd(Rational a, Rational b)
{
	Rational result;
	result.bunMo = LCM(a.bunMo, b.bunMo);
	result.bunZa = a.bunZa*(result.bunMo / a.bunMo);
	result.bunZa += b.bunZa*(result.bunMo / b.bunMo);
	return reduction(result);
}
//Subtraction
Rational RationalSub(Rational a, Rational b) {
	Rational result;
	result.bunMo = LCM(a.bunMo, b.bunMo);
	result.bunZa = a.bunZa*(result.bunMo / a.bunMo);
	result.bunZa -= b.bunZa*(result.bunMo / b.bunMo);
	return reduction(result);
}
//Multiplication
Rational RationalMul(Rational a, Rational b) {
	Rational temp;
	a = reduction(a);
	b = reduction(b);

	temp.bunMo = b.bunMo;
	temp.bunZa = a.bunZa;
	temp = reduction(temp);
	b.bunMo = temp.bunMo;
	a.bunZa = temp.bunZa;
	
	temp.bunMo = a.bunMo;
	temp.bunZa = b.bunZa;
	temp = reduction(temp);
	a.bunMo = temp.bunMo;
	b.bunZa = temp.bunZa;
	
	temp.bunMo = a.bunMo*b.bunMo;
	temp.bunZa = a.bunZa*b.bunZa;
	
	return temp;
}
//Division
Rational RationalDiv(Rational a, Rational b) {
	int temp = b.bunZa;
	b.bunZa = b.bunMo;
	b.bunMo = temp;
	return RationalMul(a, b);
}

int main()
{
	Rational a = { 2, 5 };   // 2/5 
	Rational b = { 2, 10 };  // 2/10
	Rational c, d, e, f;

	c = RationalAdd(a, b);
	printf(" e = %d/%d\n", c.bunZa, c.bunMo);

	d = RationalSub(a, b);
	printf(" d = %d/%d\n", d.bunZa, d.bunMo);

	e = RationalMul(a, b);
	printf(" e = %d/%d\n", e.bunZa, e.bunMo);

	f = RationalDiv(a, b);
	printf(" f = %d/%d\n", f.bunZa, f.bunMo);

	return 0;
}