How Big Is An int ?

Compilers may vary, but the following table captures the usual situation:

Type Specifier	length in bytes	Range	Example
`char`	1	-128 to 127	`char x;`
`unsigned char`	1	0 to 255	`unsigned char x;`
`short`	2	-32768 to 32767	`short x;` or `short int x;`
`unsigned short`	2	0 to 65535	`unsigned short x;`
`int`	4	-2147483648 to 2147483647	`int x;`
`unsigned int`	4	0 to 4294967295	`unsigned x;`
`long`	4	-2147483648 to 2147483647	`long x;` or `long int x;`
`unsigned long`	4	0 to 4294967295	`unsigned long x;`

These are reasonable since, say, 4 bytes is 32 bits and 2^32 = 4294967295

These limits are specified in the standard C library header file "limits.h"
So you can check your compiler's values using the following code:

#include <iostream>
#include <limits.h>
#include <stdlib.h>

int main(void)
{
   cout << " CHAR_MIN = " << CHAR_MIN << "CHAR_MAX = " << CHAR_MAX << endl;
   cout << " SHRT_MIN = " << SHRT_MIN << "SHRT_MAX = " << SHRT_MAX << endl;
   cout << "  INT_MIN = " << INT_MIN <<  "INT_MAX = " << INT_MAX << endl;
   cout << " LONG_MIN = " << LONG_MIN << "LONG_MAX = " << LONG_MAX << endl;
   cout << "UCHAR_MAX = " << UCHAR_MAX << endl;
   cout << "USHRT_MAX = " << USHRT_MAX << endl;
   cout << " UINT_MAX = " << UINT_MAX << endl;
   cout << " LONG_MAX = " << LONG_MAX << endl;

   system("PAUSE");
   return 0;
}

The output of this program will look like this:


 CHAR_MIN = -128, CHAR_MAX = 127
 SHRT_MIN = -32768, SHRT_MAX = 32767
  INT_MIN = -2147483648, INT_MAX = 2147483647
 LONG_MIN = -2147483648, LONG_MAX = 2147483647
UCHAR_MAX = 255
USHRT_MAX = 65535
 UINT_MAX = 4294967295
 LONG_MAX = 2147483647
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