leetcode

commit cf1189cc092fdcbcac692029e234be4ff060bcb2
parent 26ff224f42305cd88b999873c5759d0e9b396ac8
Author: AndrewLockVI <andrewlaack1@gmail.com>
Date:   Sun,  9 Apr 2023 18:06:10 -0500

Completed valid parenthesis using list as stack

Diffstat:
A
valid-parenthesis/valid-parenthesis.cpp
 | 
63
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 63 insertions(+), 0 deletions(-)
diff --git a/valid-parenthesis/valid-parenthesis.cpp b/valid-parenthesis/valid-parenthesis.cpp
@@ -0,0 +1,63 @@
+#include <iostream>
+#include <list>
+
+
+//Leet Ratings
+//       Speed  Memory
+//Total  0ms    6.4MB    
+//Beats  100%   12.9%
+
+
+using namespace std;
+
+
+//Get matching parentheses for right side.
+char get_match(char input){
+    if(input == ')'){
+        return '(';
+    }
+    if(input == '}'){
+        return '{';
+    }
+    if(input == ']'){
+        return '[';
+    }
+    return 'e';
+}
+
+//Check if parentheses are valid using a stack then checking at the end the the stack is empty.
+bool isValid(string s) {
+    list<char> stack;
+    for(int i = 0 ; i < s.size() ; ++i){
+        if(get_match(s[i]) == 'e'){
+            stack.push_front(s[i]);
+        }
+        else{
+            if(stack.front() == get_match(s[i]) ){
+                stack.pop_front();
+            }
+            else{
+                return false;
+            }
+        }
+    }
+    if(stack.empty()){
+        return true;    
+    }
+    else{
+        return false;
+    }
+}
+
+
+
+
+int main(){
+    cout << "Input parenthesis set to check: ";
+    string s;
+    cin >> s;
+    cout << boolalpha;
+    cout << isValid(s) << endl;
+
+
+}