Solution for issue #36 (#148)

* Solution for issue #1

* Create valid-parenthesis_ljsauer.py

* Delete sum-of-all-numbers_ljsauer.py

python/intermediate/valid-parenthesis_ljsauer.py

@@ -0,0 +1,57 @@
+"""
+Challenge: Given a string containing only one or more from "()[]{}"
+as input, determine if the input string is valid.
+Input is valid if:
+> Open brackets are closed by the same type of bracket
+> Open brackets are closed in the correct order
+> Input is empty
+"""
+def is_valid():
+    string = input("Enter some parentheses: ")
+
+    numOpen_p = 0
+    numClosed_p = 0
+    numOpen_k = 0
+    numClosed_k = 0
+    numOpen_c = 0
+    numClosed_c = 0
+
+    for char in string:
+        if char == '(':
+            numOpen_p +=1
+            if numClosed_p > numOpen_p:
+                return False
+        elif char == '[':
+            numOpen_k +=1
+            if numClosed_k > numOpen_k:
+                return False
+        elif char == '{':
+            numOpen_c +=1
+            if numClosed_c > numOpen_c:
+                return False
+        elif char == ')':
+            numClosed_p +=1
+            if numClosed_p >= numOpen_p:
+                return False
+        elif char == ']':
+            numClosed_k +=1
+            if numClosed_k >= numOpen_k:
+                return False
+        elif char == '}':
+            numClosed_c +=1
+            if numClosed_c >= numOpen_c:
+                return False
+        elif string == '':
+            return True
+
+    if numOpen_p > numClosed_p:
+        return False
+    elif numOpen_k > numClosed_k:
+        return False
+    elif numOpen_c > numClosed_c:
+        return False
+    else:
+        return True
+
+
+