day 14: 48-rotate-image

checked soln for this one, so doesn't actly count

48-rotate-image/driver.cpp

@@ -0,0 +1,10 @@
+#include "soln.hpp"
+
+int main()
+{
+	vector<vector<int>> matrix{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
+	vector<vector<int>> answer{{7, 4, 1}, {8, 5, 2}, {9, 6, 3}};
+	Solution soln;
+	cout << "Rotated image matrix correctly? " << soln.test(matrix, answer) << endl;
+	return 0;
+}

48-rotate-image/soln.cpp

@@ -0,0 +1,24 @@
+#include "soln.hpp"
+
+void Solution::rotate(vector<vector<int>> &matrix)
+{
+	// take your phone
+	// flip it top over bottom
+	reverse(matrix.begin(), matrix.end());
+	// then flip it across its leading diagonal
+	// voila, 90 degree rotation!
+	for (int i = 0; i < matrix.size(); i++)
+	{
+		for (int j = i; j < matrix[0].size(); j++)
+		{
+			swap(matrix[i][j], matrix[j][i]);
+		}
+	}
+}
+
+bool Solution::test(vector<vector<int>> &matrix, vector<vector<int>> &answer)
+{
+	vector<vector<int>> mat_copy(matrix);
+	rotate(mat_copy);
+	return mat_copy == answer;
+}

48-rotate-image/soln.hpp

@@ -0,0 +1,8 @@
+#include <bits/stdc++.h>
+using namespace std;
+class Solution
+{
+public:
+	void rotate(vector<vector<int>> &matrix);
+	bool test(vector<vector<int>> &matrix, vector<vector<int>> &answer);
+};