Python: Validity of a string of parentheses
Write a Python class to check the validity of a string of parentheses, '(', ')', '{', '}', '[' and ']. These brackets must be closed in the correct order,
for example "()" and "()[]{}" are valid but "[)", "({[)]" and "{{{" are invalid.
Sample Solution:
Python Code:
class py_solution:
def is_valid_parenthese(self, str1):
stack, pchar = [], {"(": ")", "{": "}", "[": "]"}
for parenthese in str1:
if parenthese in pchar:
stack.append(parenthese)
elif len(stack) == 0 or pchar[stack.pop()] != parenthese:
return False
return len(stack) == 0
print(py_solution().is_valid_parenthese("(){}[]"))
print(py_solution().is_valid_parenthese("()[{)}"))
print(py_solution().is_valid_parenthese("()"))
Sample Output:
True False True
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Flowchart:
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