[user02@FC4 Lesson07]$ cat -n cin_long.cpp

   1  #include <iostream>
   2  using namespace std;
   3
   4  int main()
   5  {
   6     long value;
   7
   8     cout << "Type a large number and press Enter: ";
   9     cin >> value;
  10     cout << "The number you typed was " << value << endl;
  11
  12     return 0;
  13  }

[user02@FC4 Lesson07]$ g++ -o cin_long cin_long.cpp
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: 4000000
The number you typed was 4000000
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: 500000000
The number you typed was 500000000
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: 50000000000000
The number you typed was 11246752
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: -9999999999999
The number you typed was 11246752
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: abc
The number you typed was 11246752
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: 34.56
The number you typed was 34
[user02@FC4 Lesson07]$ ./cin_long
Type a large number and press Enter: .45
The number you typed was 11246752
[user02@FC4 Lesson07]$