Array checksum question

What is the largest number that will fit in an int?

I suppose the largest number that will fit in int is around 10 ^ 500000.

After this my python said memory overflow.

My question was directed at leeUNAGI, who is using C++.

I just wanted to give you a tip that your question is not quite correct.

There are a lot of different ints, so you must be more specific.

Do you at least know that C++ size of int is different for 32-bit and 64-bit systems?

By the way, leeUNAGI, I looked into your solution and want to share some insights on coding style:

1. Be consistent on your coding style. For example, you surround operators with spaces at some places, but you do not surround them in other places, can you explain why?
2. Never declare integer variables with bare int. This is a bad habit because the program will compile differently on different platforms. On 16-bit platforms it will compile with 16-bit ints, on 32-bit platforms with 32-bit ints, and on 64-bit platforms with 64-bit ints. And I believe that 128-bit platforms are on the way. So be explicit:
   -declare 16-bit ints as signed short int or unsigned short int
   -declare 32-bit ints as signed long int or unsigned long int
   -declare 64-bit ints as signed long long or unsigned long long
3. If you see that the value of some variable will never change, then this is not a variable, but a constant. Declare constants with a const keyword. For example, limit and seed variables in your program are actually constants.
4. After you finished program, look carefully if there are any unused declarations left. For example, do you see where you use the a or index variables? Yeah, they are never used anymore. So remove unnecessary declarations.

For example there are first ten lines of your program nicely coded:

#include <iostream>
#include <fstream>
using namespace std;

ifstream fileIN1("array_checksum.data");
ofstream fileOUT1("array_checksum.sum.out");

int main() {

    const signed long int seed = 113;
    const signed long int limit = 10000007;

    signed long int ct, result = 0;
    signed long int arr[1000];
    ...

qwerty

The size of a short, int, long and long long are determined by the C++ compiler.

Running this C++ code, on a codeabbey problem page

#include<iostream>
using namespace std;

int main(){
  signed long int a;
  signed long long b;
  cout << sizeof(a) << " "  << sizeof(b) << endl;
}

gives 8 8, showing that a signed long int and a signed long long are the same size!

But perhaps if I declare variable as signed long int, it will be -at least- 32-bit size? That's what I meant...

I'm sorry to hear that.

I wish I could say some words to support you, but I'm not good enough at english.