Question

include<iostream>
#include<cstring>

using namespace std;
char reg[30];
int main()
{
   //char reg[30];
   char DNA[30];
   int flag = 0;
   int n, ni, i, j, k;

   cout << "Enter a regular expression" << ;
   cin >> reg;
   cout << endl;

   n = reg.size();
   for (int i = 0; i < n; i++)
   {
       strcpy(DNA, reg.substr(i, j));
       ni = DNA.lenghth();
       for (k = 0; k < ni; k++)
       {
           if (DNA[i] == 'A')
               flag = flag + 1;
       }
       if (flag >= 2)
           cout << DNA << endl;
   }
   return 0;
}

Please help my code won't work

Answer 1

`Hey,

Note: If you have any queries related the answer please do comment. I would be very happy to resolve all your queries.

Please note there were many syntax errors I have changed char array to string since substr works for string

#include<iostream>
#include<cstring>

using namespace std;
string reg;
int main()
{
//char reg[30];
int flag = 0;
int n, ni, i, j, k;

cout << "Enter a regular expression: ";
cin >> reg;
cout << endl;

n = reg.length();
for (int i = 0; i < n; i++)
{ string DNA;
string temp=reg.substr(i, j);
DNA=temp;
ni =DNA.length();
for (k = 0; k < ni; k++)
{
if (DNA[i] == 'A')
flag = flag + 1;
}
if (flag >= 2)
cout << DNA<<endl;
}
return 0;
}

Kindly revert for any queries

Thanks.