Q.7: How to find all possible substring of a given string?

 Ans.: This is a very frequent interview question. Here we need to form all the possible substrings from input string, varying from length 1 to the input string length. The output will include the input string also.

• input: abcd , output : a ab abc abcd b bc bcd c cd d

internal static void findallsubstring(string str)

{

for (int i = 0; i < str.Length; ++i)

{

StringBuilder subString = new StringBuilder(str.Length - i);

for (int j = i; j < str.Length; ++j)

{

subString.Append(str[j]);

Console.Write(subString + " ");

}

}

}