The following code uses the obvious approach described in the problem statement that examines all of the first string's possible substrings:
// Find the longest substring by examining every possible// substring in string1.private string FindLongestSubstring1(string string1, string string2){ string bestSubstring = ""; int bestLength = 0; // Loop over all possible starting positions. for (int startPos = 0; startPos < string1.Length - 1; startPos++) { // Loop over possible lengths starting at this position. for (int length = bestLength + 1; length <= string1.Length - startPos; length++) { string testSubstring = string1.Substring(startPos, length); int testPos = string2.IndexOf(testSubstring); if (testPos >= 0) { ...
