unsigned long : unsigned long « Data Types « C++ Tutorial

1. C++ Tutorial
2. Data Types
3. unsigned long

#include<iostream.h>

main()
{
  int n = 123;
  unsigned long factor=1;

  for(int i=n;i>1;i--)
    factor=factor*i;

  cout<<n<<"!="<<factor<<endl;
  return 0;
}

123!=0