day 24: 36-valid-sudoku, 128-longest-consecutive-sequence

128-longest-consecutive-sequence/driver.cpp

@@ -0,0 +1,10 @@
+#include "soln.hpp"
+
+int main()
+{
+	vector<int> nums{100, 4, 200, 1, 3, 2};
+	int answer = 4;
+	Solution soln;
+	cout << "Found longest consecutive sequence correctly? " << soln.test(nums, answer) << endl;
+	return 0;
+}

128-longest-consecutive-sequence/soln.cpp

@@ -0,0 +1,27 @@
+#include "soln.hpp"
+
+int Solution::longestConsecutive(vector<int> &nums)
+{
+	if (nums.size() < 2)
+		return nums.size();
+	sort(nums.begin(), nums.end());
+	int max_len = 1, cur_max_len = 1;
+	for (int i = 1; i < nums.size(); i++)
+	{
+		if (nums[i] == nums[i - 1])
+			continue;
+		if ((nums[i] == nums[i - 1] + 1))
+			cur_max_len++;
+		else
+		{
+			max_len = max(cur_max_len, max_len);
+			cur_max_len = 1;
+		}
+	}
+	return max(max_len, cur_max_len);
+}
+
+bool Solution::test(vector<int> &nums, int answer)
+{
+	return longestConsecutive(nums) == answer;
+}

128-longest-consecutive-sequence/soln.hpp

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

36-valid-sudoku/driver.cpp

@@ -0,0 +1,21 @@
+#include "soln.hpp"
+
+int main()
+{
+	vector<vector<char>> board{
+		{'5', '3', '.',		'.', '7', '.',		'.', '.', '.'},
+		{'6', '.', '.',		'1', '9', '5',		'.', '.', '.'},
+		{'.', '9', '8',		'.', '.', '.',		'.', '6', '.'},
+
+		{'8', '.', '.',		'.', '6', '.',		'.', '.', '3'},
+		{'4', '.', '.',		'8', '.', '3',		'.', '.', '1'},
+		{'7', '.', '.',		'.', '2', '.',		'.', '.', '6'},
+		
+		{'.', '6', '.',		'.', '.', '.',		'2', '8', '.'},
+		{'.', '.', '.',		'4', '1', '9',		'.', '.', '5'},
+		{'.', '.', '.',		'.', '8', '.',		'.', '7', '9'}};
+	bool answer = true;
+	Solution soln;
+	cout << "Validated sudoku correctly? " << soln.test(board, answer) << endl;
+	return 0;
+}

36-valid-sudoku/soln.cpp

@@ -0,0 +1,57 @@
+#include "soln.hpp"
+
+bool Solution::isValidSudoku(vector<vector<char>> &board)
+{
+	unordered_map<char, bool> appeared;
+	// check rows
+	for (int i = 0; i < 9; i++)
+	{
+		appeared.clear();
+		for (int j = 0; j < 9; j++)
+		{
+			char checker = board[i][j];
+			if (checker == '.')
+				continue;
+			if (appeared.find(checker) != appeared.end())
+				return false;
+			appeared[checker] = true;
+		}
+	}
+	// check columns
+	for (int i = 0; i < 9; i++)
+	{
+		appeared.clear();
+		for (int j = 0; j < 9; j++)
+		{
+			char checker = board[j][i];
+			if (checker == '.')
+				continue;
+			if (appeared.find(checker) != appeared.end())
+				return false;
+			appeared[checker] = true;
+		}
+	}
+	// check grids
+	for (int i = 0; i < 9; i++)
+	{
+		appeared.clear();
+		for (int j = 0; j < 3; j++)
+		{
+			for (int k = 0; k < 3; k++)
+			{
+				char checker = board[((i / 3) * 3) + j][((i * 3) % 9) + k];
+				if (checker == '.')
+					continue;
+				if (appeared.find(checker) != appeared.end())
+					return false;
+				appeared[checker] = true;
+			}
+		}
+	}
+	return true;
+}
+
+bool Solution::test(vector<vector<char>> &board, bool answer)
+{
+	return isValidSudoku(board) == answer;
+}

36-valid-sudoku/soln.hpp

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