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bluurn/main.cpp

Created February 26, 2019 14:38
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CPP: Implementation of Rational
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main.cpp
#include <iostream>
#include <sstream>
#include <cmath>
#include <map>
#include <vector>
#include <set>
using namespace std;
class Rational {
public:
Rational() {
numerator = 0;
denominator = 1;
}
Rational(int numerator, int denominator) {
int gcd_modulo = gcd(abs(numerator), abs(denominator));
if (numerator != 0) {
if (denominator > 0) {
this->numerator = numerator / gcd_modulo;
this->denominator = denominator / gcd_modulo;
} else {
this->numerator = -(numerator / gcd_modulo);
this->denominator = -(denominator / gcd_modulo);
}
} else {
this->numerator = numerator;
this->denominator = 1;
}
}
int Numerator() const {
return numerator;
}
int Denominator() const {
return denominator;
}
private:
int gcd(int a, int b) {
while (a > 0 && b > 0) {
if (a > b) {
a %= b;
} else {
b %= a;
}
}
return a + b;
}
signed int numerator;
int denominator;
};
bool operator==(const Rational &lhs, const Rational &rhs) {
return lhs.Numerator() == rhs.Numerator() && lhs.Denominator() == rhs.Denominator();
}
bool operator<(const Rational &lhs, const Rational &rhs) {
return lhs.Numerator() * rhs.Denominator() < rhs.Numerator() * lhs.Denominator();
}
Rational operator+(const Rational &lhs, const Rational &rhs) {
return {
lhs.Numerator() * rhs.Denominator() + rhs.Numerator() * lhs.Denominator(),
lhs.Denominator() * rhs.Denominator()
};
}
Rational operator-(const Rational &lhs, const Rational &rhs) {
return {
lhs.Numerator() * rhs.Denominator() - rhs.Numerator() * lhs.Denominator(),
lhs.Denominator() * rhs.Denominator()
};
}
Rational operator*(const Rational &lhs, const Rational &rhs) {
return {
lhs.Numerator() * rhs.Numerator(),
lhs.Denominator() * rhs.Denominator()
};
}
Rational operator/(const Rational &lhs, const Rational &rhs) {
return {
lhs.Numerator() * rhs.Denominator(),
lhs.Denominator() * rhs.Numerator()
};
}
ostream& operator<<(ostream &stream, const Rational &rational) {
stream << rational.Numerator()
<< "/"
<< rational.Denominator();
return stream;
}
istream& operator>>(istream& stream, Rational& rational) {
if (stream.tellg() == -1) {
return stream;
}
int numerator = 0;
int denominator = 1;
stream >> numerator;
stream.ignore(1);
stream >> denominator;
Rational new_rational = Rational { numerator, denominator };
rational = new_rational;
return stream;
}
int main() {
{
const Rational r(3, 10);
if (r.Numerator() != 3 || r.Denominator() != 10) {
cout << "Rational(3, 10) != 3/10" << endl;
return 1;
}
}
{
const Rational r(8, 12);
if (r.Numerator() != 2 || r.Denominator() != 3) {
cout << "Rational(8, 12) != 2/3" << endl;
return 2;
}
}
{
const Rational r(-4, 6);
if (r.Numerator() != -2 || r.Denominator() != 3) {
cout << "Rational(-4, 6) != -2/3" << endl;
return 3;
}
}
{
const Rational r(4, -6);
if (r.Numerator() != -2 || r.Denominator() != 3) {
cout << "Rational(4, -6) != -2/3" << endl;
return 3;
}
}
{
const Rational r(0, 15);
if (r.Numerator() != 0 || r.Denominator() != 1) {
cout << "Rational(0, 15) != 0/1" << endl;
return 4;
}
}
{
const Rational defaultConstructed;
if (defaultConstructed.Numerator() != 0 || defaultConstructed.Denominator() != 1) {
cout << "Rational() != 0/1" << endl;
return 5;
}
}
{
const Rational r(-6, -8);
if (r.Numerator() != 3 || r.Denominator() != 4) {
cout << "Rational(-6, -8) != 2/3" << endl;
return 6;
}
}
{
Rational r1(4, 6);
Rational r2(2, 3);
bool equal = r1 == r2;
if (!equal) {
cout << "4/6 != 2/3" << endl;
return 1;
}
}
{
Rational a(2, 3);
Rational b(4, 3);
Rational c = a + b;
bool equal = c == Rational(2, 1);
if (!equal) {
cout << "2/3 + 4/3 != 2" << endl;
return 2;
}
}
{
Rational a(5, 7);
Rational b(2, 9);
Rational c = a - b;
bool equal = c == Rational(31, 63);
if (!equal) {
cout << "5/7 - 2/9 != 31/63" << endl;
return 3;
}
}
{
Rational a(2, 3);
Rational b(4, 3);
Rational c = a * b;
bool equal = c == Rational(8, 9);
if (!equal) {
cout << "2/3 * 4/3 != 8/9" << endl;
return 1;
}
}
{
Rational a(5, 4);
Rational b(15, 8);
Rational c = a / b;
bool equal = c == Rational(2, 3);
if (!equal) {
cout << "5/4 / 15/8 != 2/3" << endl;
return 2;
}
}
{
ostringstream output;
output << Rational(-6, 8);
if (output.str() != "-3/4") {
cout << "Rational(-6, 8) should be written as \"-3/4\"" << endl;
return 1;
}
}
{
istringstream input("5/7");
Rational r;
input >> r;
bool equal = r == Rational(5, 7);
if (!equal) {
cout << "5/7 is incorrectly read as " << r << endl;
return 2;
}
}
{
istringstream input("5/7 10/8");
Rational r1, r2;
input >> r1 >> r2;
bool correct = r1 == Rational(5, 7) && r2 == Rational(5, 4);
if (!correct) {
cout << "Multiple values are read incorrectly: " << r1 << " " << r2 << endl;
return 3;
}
input >> r1;
input >> r2;
correct = r1 == Rational(5, 7) && r2 == Rational(5, 4);
if (!correct) {
cout << "Read from empty stream shouldn't change arguments: " << r1 << " " << r2 << endl;
return 4;
}
}
{
const set<Rational> rs = {{1, 2}, {1, 25}, {3, 4}, {3, 4}, {1, 2}};
if (rs.size() != 3) {
cout << "Wrong amount of items in the set" << endl;
return 1;
}
vector<Rational> v;
for (auto x : rs) {
v.push_back(x);
}
if (v != vector<Rational>{{1, 25}, {1, 2}, {3, 4}}) {
cout << "Rationals comparison works incorrectly" << endl;
return 2;
}
}
{
map<Rational, int> count;
++count[{1, 2}];
++count[{1, 2}];
++count[{2, 3}];
if (count.size() != 2) {
cout << "Wrong amount of items in the map" << endl;
return 3;
}
}
cout << "OK" << endl;
return 0;
}
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