day 17: 189-rotate-array

189-rotate-array/driver.cpp

@@ -0,0 +1,11 @@
+#include "soln.hpp"
+
+int main()
+{
+	vector<int> nums = {1, 2, 3, 4, 5, 6, 7};
+	int k = 9;
+	vector<int> answer = {6, 7, 1, 2, 3, 4, 5};
+	Solution soln;
+	cout << "Rotated array correctly? " << soln.test(nums, k, answer) << endl;
+	return 0;
+}

189-rotate-array/soln.cpp

@@ -0,0 +1,20 @@
+#include "soln.hpp"
+
+void Solution::rotate(vector<int> &nums, int k)
+{
+	int n = nums.size();
+	if (n != 1)
+	{
+		k %= n;
+		vector<int> result(nums.begin() + (nums.size() - k), nums.end());
+		result.insert(result.end(), nums.begin(), nums.end() - k);
+		nums = result;
+	}
+}
+
+bool Solution::test(vector<int> &nums, int k, vector<int> &answer)
+{
+	vector<int> nums_copy(nums);
+	rotate(nums_copy, k);
+	return nums_copy == answer;
+}

189-rotate-array/soln.hpp

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