Question

I am trying to make a code to allow the user to enter a very huge number “bigger than the size of the normal “int” , so am trying to take the user input as a string and take each value from the string and pass it to an int e.g. s="3786473646768" so int will take each value and save it in a vector.

This is a very simple syntax I enter the two strings but if they aren’t equal it gives me a window saying “Expression: String Subscript is out of range”
Any help please ?

#include "stdafx.h"
#include <iostream>
#include <sstream>
#include <string>
#include <vector>

using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{

  int val1=0,val2=0,val3=0,val4=0;
  string i,p;
  vector <int>add;
  vector <int>sub; 
  cout<<"Enter a number: "<<endl;
  cin>>i;
  int sizei=i.length();
  cout<<"Enter a number: "<<endl;
  cin>>p;
  int sizep=p.length();

  for (int n=0; n<sizei; n++)
   {
     val1=int(i[n]);
     val1=val1-48;
     val2=int(p[n]);
     val2=val2-48;
     val3=val1+val2;
     val4=val1-val2;
     add.push_back(val3);
     sub.push_back(val4);
   }
  cout<<"\n";
  for(unsigned int a=0;a<add.size();a++)
      cout<<add.at(a);
  cout<<"\n";
  for(unsigned int a=0;a<sub.size();a++)
      cout<<sub.at(a);
    system("pause");
    return 0;
}

Answer 1

for (int n=0; n<sizei; n++)

Within this loop, the value of n goes from 0 ... sizei - 1

However, if sizep is less than sizei - 1, it will try to access p[n] or equivalently, p[sizei-1], which is outside the bounds of the string you declared.