add exercise

Author: charliesbot

cpp/0001_two_sum/0001_two_sum.cc

@@ -3,7 +3,6 @@
 #include <unordered_map>
 #include <vector>
 
-using std::cout;
 using std::unordered_map;
 using std::vector;
 

cpp/0001_two_sum/0001_two_sum_test.cc

@@ -1,4 +1,4 @@
-#include "cpp/0001_two_sum/0001_two_sum.h"
+#include "0001_two_sum.h"
 #include <gtest/gtest.h>
 #include <vector>
 

cpp/0020_valid_parentheses/0020_valid_parentheses.cc

@@ -0,0 +1,36 @@
+#include "0020_valid_parentheses.h"
+#include <iostream>
+#include <stack>
+#include <string>
+#include <unordered_map>
+
+using std::stack;
+using std::unordered_map;
+
+bool Solution::isValid(string s) {
+  unordered_map<char, char> dict({{'(', ')'}, {'[', ']'}, {'{', '}'}});
+  stack<char> stack;
+    std::cout << "heyyy" << "\n";
+
+  for (const char &letter : s) {
+    std::cout << "heyyy" << "\n";
+    if (dict.find(letter) != dict.end()) {
+      stack.push(dict[letter]);
+      continue;
+    }
+
+    if (stack.empty()) {
+        return false;
+    }
+
+    const char& popped = stack.top();
+
+    if (letter != popped) {
+      return false;
+    }
+
+    stack.pop();
+  }
+
+  return stack.empty();
+}

cpp/0020_valid_parentheses/0020_valid_parentheses.h

@@ -0,0 +1,9 @@
+#include <stdio.h>
+#include <string>
+
+using std::string;
+
+class Solution {
+public:
+    bool isValid(string s);
+};

cpp/0020_valid_parentheses/0020_valid_parentheses_test.cc

@@ -0,0 +1,29 @@
+#include "0020_valid_parentheses.h"
+#include <gtest/gtest.h>
+#include <string>
+
+using std::string;
+
+TEST(ValidParenthesisTest, SimpleString) {
+  string s = "()";
+
+  ASSERT_TRUE(Solution().isValid(s));
+}
+
+TEST(ValidParenthesisTest, AllSymbolsString) {
+  string s = "()[]{}";
+
+  ASSERT_TRUE(Solution().isValid(s));
+}
+
+TEST(ValidParenthesisTest, InvalidString) {
+  string s = "(]";
+
+  ASSERT_FALSE(Solution().isValid(s));
+}
+
+TEST(ValidParenthesisTest, InvalidString2) {
+  string s = "]";
+
+  ASSERT_FALSE(Solution().isValid(s));
+}

cpp/0200_number_of_islands/0200_number_of_islands.cc

@@ -2,7 +2,6 @@
 #include <iostream>
 #include <vector>
 
-using std::cout;
 using std::vector;
 
 void dfs(vector<vector<char>> &grid, size_t row, size_t column) {

cpp/0200_number_of_islands/0200_number_of_islands.h

@@ -5,5 +5,4 @@ using std::vector;
 class Solution {
 public:
   int numIslands(vector<vector<char>> &grid);
-}
-;
+};

cpp/0200_number_of_islands/0200_number_of_islands_test.cc

@@ -1,4 +1,4 @@
-#include "cpp/0200_number_of_islands/0200_number_of_islands.h"
+#include "0200_number_of_islands.h"
 #include <gtest/gtest.h>
 #include <vector>