Question

Arrays,Lists, Stacks and queues

1) Describe a recursive function to convert a string of digits into the integer it represents. For example, the string “3735928559” would be converted to the integer value 3,735,928,559.[Preferrably in C++]

Answer 1

// Datatype used in this program is long. It can be changed according to requirements.

#include <iostream>
#include <string>
#include <typeinfo>
using namespace std;

long p = 0;
long c;
void convert(string str)
{
  
  
   if(str.size() == 0)
   {
       return;
   }
   c = str[0]-'0'; //    for type conversion (char to int)
  
p = p*10+c;
   convert(str.substr(1));
  
}

int main()
{
string a;
cin >> a;
// Check the type of input using (cout << typeid(a).name() << endl;)
   convert(a);
//    Check the type of output using (cout << typeid(p).name() << endl;) => gives l which means long int
   cout << p;
}