public void Execute(string s, int startingPos)
{
int parenthesesCounter = 0;
Valid = true;
for (int i = startingPos; i < s.Length && Valid; i++)
{
if (s[i] == OpeningChar)
{
parenthesesCounter++;
}
else if (s[i] == ClosingChar)
{
parenthesesCounter--;
if (parenthesesCounter < 0)
{
Valid = false;
}
}
else
{
if (parenthesesCounter == 0)
{
return;
}
else if (!ClosingParenthesisDict.ContainsKey(s[i]))
{
Valid = false;
}
else
{
ValidParentheses subProblem = new ValidParentheses
{
OpeningChar = s[i],
ClosingChar = ClosingParenthesisDict[s[i]]
};
subProblem.Execute(s, i);
Valid = subProblem.Valid;
i = subProblem.LastPosition;
}
}
LastPosition = i;
}
if (parenthesesCounter > 0)
{
Valid = false;
}
}
public bool IsValid(string s)
{
if (s.Equals(string.Empty))
{
return(true);
}
if (!ClosingParenthesisDict.ContainsKey(s[0]))
{
return(false);
}
ValidParentheses problem = new ValidParentheses
{
OpeningChar = s[0],
ClosingChar = ClosingParenthesisDict[s[0]],
};
problem.Execute(s, 0);
if (!problem.Valid)
{
return(false);
}
while (problem.LastPosition != s.Length - 1)
{
int pos = problem.LastPosition + 1;
if (!ClosingParenthesisDict.ContainsKey(s[pos]))
{
return(false);
}
problem = new ValidParentheses
{
OpeningChar = s[pos],
ClosingChar = ClosingParenthesisDict[s[pos]],
};
problem.Execute(s, pos);
if (!problem.Valid)
{
return(false);
}
}
return(true);
}