Similar String algorithm

Question

I\'m looking for an algorithm, or at least theory of operation on how you would find similar text in two or more different strings...

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Answer 1

i had a similar problem, i needed to get the percentage of characters in a string that were similar. it needed exact sequences, so for example "hello sir" and "sir hello" when compared needed to give me five characters that are the same, in this case they would be the two "hello"'s. it would then take the length of the longest of the two strings and give me a percentage of how similar they were. this is the code that i came up with

int compare(string a, string b){
   return(a.size() > b.size() ? bigger(a,b) : bigger(b,a));
}



int bigger(string a, string b){



int maxcount = 0, currentcount = 0;//used to see which set of concurrent characters were biggest

for(int i = 0; i < a.size(); ++i){

    for(int j = 0; j < b.size(); ++j){

        if(a[i+j] == b[j]){

         ++currentcount;

         }

        else{

            if(currentcount > maxcount){

             maxcount = currentcount;

             }//end if

             currentcount = 0;

            }//end else

        }//end inner for loop

    }//end outer for loop


   return ((int)(((float)maxcount/((float)a.size()))*100));
}