[w7] Added exercise descriptions and solutions

1 files changed, 83 insertions, 0 deletions

diff --git a/week07/Exercise6.cpp b/week07/Exercise6.cpp
new file mode 100644
index 0000000..200f4d8
--- /dev/null
+++ b/week07/Exercise6.cpp
@@ -0,0 +1,83 @@
+#include "Exercise6.h"
+#include <iostream>
+
+/* Private */
+
+void Matrix::addBy(int amount) {
+	for (int i = 0; i < 4; i++) {
+		values[i] += amount;
+	}
+}
+
+/* Public */
+
+Matrix::Matrix(int a, int b, int c, int d) {
+	values[0] = a;
+	values[1] = b;
+	values[2] = c;
+	values[3] = d;
+}
+
+Matrix& Matrix::operator++() { // ++matrix
+	addBy(+1);
+	return *this;
+}
+Matrix Matrix::operator++(int) { // matrix++
+	Matrix copy = *this;
+	addBy(+1);
+	return copy;
+}
+Matrix& Matrix::operator--() { // --matrix
+	addBy(-1);
+	return *this;
+}
+Matrix Matrix::operator--(int) { // matrix--
+	Matrix copy = *this;
+	addBy(-1);
+	return copy;
+}
+
+Matrix& Matrix::operator+=(const Matrix& rhs) {
+	for (int i = 0; i < 4; i++) {
+		values[i] += rhs.values[i];
+	}
+	return *this;
+}
+Matrix& Matrix::operator-=(const Matrix& rhs) {
+	for (int i = 0; i < 4; i++) {
+		values[i] -= rhs.values[i];
+	}
+	return *this;
+}
+Matrix& Matrix::operator*=(const Matrix& rhs) {
+	values[0] = values[0] * rhs.values[0] + values[1] * rhs.values[2];
+	values[1] = values[0] * rhs.values[1] + values[1] * rhs.values[3];
+	values[2] = values[2] * rhs.values[0] + values[3] * rhs.values[2];
+	values[3] = values[2] * rhs.values[1] + values[3] * rhs.values[3];
+	return *this;
+}
+
+/* Friend */
+
+Matrix operator+(const Matrix& lhs, const Matrix& rhs) {
+	Matrix ret = lhs;
+	ret += rhs;
+	return ret;
+}
+Matrix operator-(const Matrix& lhs, const Matrix& rhs) {
+	Matrix ret = lhs;
+	ret -= rhs;
+	return ret;
+}
+Matrix operator*(const Matrix& lhs, const Matrix& rhs) {
+	Matrix ret = lhs;
+	ret *= rhs;
+	return ret;
+}
+
+std::ostream& operator<<(std::ostream& lhs, const Matrix& rhs) {
+	return lhs << rhs.values[0] << "," << rhs.values[1] << std::endl << rhs.values[2] << "," << rhs.values[3] << std::endl;
+}
+std::istream& operator>>(std::istream& lhs, Matrix& rhs) {
+	return lhs >> rhs.values[0] >> rhs.values[1] >> rhs.values[2] >> rhs.values[3];
+}