My first Leetcode experience and achievement

Started to play with Leetcode problems. Pretty addictive activity. The first task I selected was “Longest Substring Without Repeating Characters“. I wrote the code in C# and got a result – 22.9% in “Accepted Solutions Runtime Distribution”. It means that my solution has beaten only one fifth of other submitted implementations. I reprogrammed in C++ and achieved 84%. So it was surprise for me, because I did not expect such difference in my C# and C++ skills.

The code:

class Solution {
public:
   int lengthOfLongestSubstring(string s)
   {
	int len = 0;
	int lenstr = s.length();
	if (lenstr)
	{
		const char * substr = s.c_str();
		const char * distinct = new char[lenstr+1];
		for (int i = 0; i < lenstr; i++)
		{
			memset((void*)distinct, 0, lenstr + 1);
			char * distincttmp = (char*)distinct;
			int times = 0;
			const char * ch = substr;
			for (int k = 0; k < lenstr; k++)
			{
				const char * pch = strrchr(distinct, *ch);
				if (!pch)
				{
					*distincttmp = *ch;
					distincttmp++;
					if (times) break;
				}
				else
					times++;
				ch++;
			}
			ch = substr;
			char * distincttmp1 = (char*)distinct;
			while (*distincttmp1)
			{
				if (*ch != *distincttmp1)
					break;
				distincttmp1++;
				ch++;
			}
			int j = ch - substr;
			substr++;
			if (j == 0) continue;
			if ((!len) && (j == distincttmp - distinct))
			{
				return j;
			}
			if (j > len)
			{
				len = j;
			}
			if ((lenstr - i) <= j)
				break;
		}
		delete[] distinct;
	}
	return len;
   }
}