Range of Int in C

The range of the int data type is implementation-dependent, which means it can vary from one C compiler and system to another. However, the C standard (as of C99 and C11) specifies minimum requirements for the range of int.

The C standard specifies that an int must have a minimum range of at least -32,767 to +32,767 (i.e., -2^15+1 to 2^15-1) for a two’s complement system. This corresponds to 16 bits, where one bit is used to represent the sign (positive or negative) of the integer.

Here’s the general formula for calculating the range of int on a two’s complement system:

• Minimum int value: -2^(n-1) where n is the number of bits used for int.
• Maximum int value: 2^(n-1) – 1

For example, on most modern systems, including those using the x86 architecture, the int data type typically has a range of -2,147,483,647 to +2,147,483,647 for a 32-bit int, and -9,223,372,036,854,775,807 to +9,223,372,036,854,775,807 for a 64-bit int.

To determine the exact range of int on your specific system, you can use the limits.h header and check the values of INT_MIN and INT_MAX. For example:

#include <stdio.h>
#include <limits.h>

int main() {
    printf("Minimum int value: %d\n", INT_MIN);
    printf("Maximum int value: %d\n", INT_MAX);

    return 0;
}

This program will print the minimum and maximum values of the int data type for your specific system.