How to find large consecutive substring from a string.

[mudassar24]

Hi,
please tell me how i can find large consecutive substring from a string.
For Example:
Input is : ABCQWERSTUVWNOL
out put should be: RSTUVW

[bradw]

Try strstr().
http://www.cplusplus.com/reference/clibrary/cstring/strstr/

Unless you are supposed to write your own substring search. If so, to get you going in the right direction think about how you would find a string inside a string. I would begin by trying to find the first letter of the string I'm looking for inside of the string I'm searching through.

[Athar]

Just keep track of the current substring length (and start position) and if a character doesn't match, reset it to one.

[hamsterman]

@bradw, he's not looking for a known string, but for a part of alphabet.

@OP, There are several ways to write this. I'll give you the least efficient one:

const char* str = "ABCQWERSTUVWNOL";
for (int i = 0; str[i] != 0; i++) //for each char in str...
   for (int j = 1; str[i+j] - str[i] == j; j++) //the condition means 'while characters progress in a linear way'
      //if this line is executed, you've found several consecutive chars between indexes i and i+j
      //you'll want to have a "char* start" and "int length" outside the loops to remember the longest of them. 

Notice that some characters are processed several times. You really only need one loop (or one counter).