Ex_2.1_cal_limits.c

/***
 *
 * Exercise 2.1
 *
 * Program to print maximum, minimum limits of char, int, long using
 * calculation
 *
 ***/

/* The logic used is
* ~0 will give bits in 1s.
* (unsigned <type>) will cast it unsigned.
* >> 1 right shifts 1 bit to remove the sign bit.
* (<type>) casting it the required type again
*/

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

int main(void)
{
	/* ranges of various floating-point types through calculation */
	printf("Ranges of various floating-point types through calculation:\n");
	
	printf("Minimum Signed Char %d\n",-(char)((unsigned char) ~0 >> 1) - 1);
	printf("Maximum Signed Char %d\n",(char) ((unsigned char) ~0 >> 1));

	printf("Minimum Signed Short %d\n",-(short)((unsigned short)~0 >>1) -1);
	printf("Maximum Signed Short %d\n",(short)((unsigned short)~0 >> 1));

	printf("Minimum Signed Int %d\n",-(int)((unsigned int)~0 >> 1) -1);
	printf("Maximum Signed Int %d\n",(int)((unsigned int)~0 >> 1));

	printf("Minimum Signed Long %ld\n",-(long)((unsigned long)~0 >>1) -1);
	printf("Maximum signed Long %ld\n",(long)((unsigned long)~0 >> 1));

	/* Unsigned Maximum Values */

	printf("Maximum Unsigned Char %d\n",(unsigned char)~0);
	printf("Maximum Unsigned Short %d\n",(unsigned short)~0);
	printf("Maximum Unsigned Int %u\n",(unsigned int)~0);
	printf("Maximum Unsigned Long %lu\n\n",(unsigned long)~0);
	
	/* ranges of various floating-point types from standard headers */
	printf("Ranges of various floating-point types from standard headers:\n");
	
	printf("Minimum Signed Char %d\n", SCHAR_MIN);
    	printf("Maximum Signed Char %d\n", SCHAR_MAX);
    
    	printf("Minimum Signed Short %d\n", SHRT_MIN);
    	printf("Maximum Signed Short %d\n", SHRT_MAX);
    
    	printf("Minimum Signed Int %d\n", INT_MIN);
    	printf("Maximum Signed Int %d\n", INT_MAX);
    
    	printf("Minimum Signed Long %ld\n", LONG_MIN);
    	printf("Maximum signed Long %ld\n", LONG_MAX);
    
    	/* Unsigned Maximum Values */
    
    	printf("Maximum Unsigned Char %d\n", UCHAR_MAX);
    	printf("Maximum Unsigned Short %d\n", USHRT_MAX);
    	printf("Maximum Unsigned Int %u\n", UINT_MAX);
    	printf("Maximum Unsigned Long %lu\n", ULONG_MAX);
    	
	return 0;
}