/* Single-Precision Floating-Point Numbers

Just like we learned in class, floating-point numbers are stored 
in the IEEE 754 format. 

Write a C program that reads a 32-bit single-precision binary number 
and prints its value using the "%g" formatting inside printf.

HINT: It may be easier to read the values of the individual bits as 
characters, and calculate the sign-bit, the 8 exponent bits, and 
the 23-bit mantissa bits separately.


============== Sample Output 1 ===============
Enter a single-precision binary number:

00111110001000000000000000000000

The value entered is: 0.15625
==============================================



============== Sample Output 2 ===============
Enter a single-precision binary number:

11000011110010010001000000100000

The value entered is: -402.126
==============================================


============== Sample Output 3 ===============
Enter a single-precision binary number:

01000000011000000000000000000000

The value entered is: 3.5
==============================================



*/

#include <stdlib.h>
#include <stdio.h>
#include <math.h>

int main(int argc, char *argv[])
{
	// Declare variables
	char c;
	int sign, counter;
	double exponent=0, mantissa=1, placeVal;
	
	// Gather input from user
	printf("Enter a single-precision binary number:\n\n");
	scanf("%c", &c);
	// PROCESS SIGN BIT: If sign bit= 0 then 1, else -1
	sign = (c=='0')?1:-1; 
	
	// PROCESS EXPONENT: While scanning in the 8 exponent values, if
	// a value is 1, it adds the value of that place to the exponent 
	// variable. Exponent was initialized to - to accumulate correct value
	for(counter=0, placeVal=128; counter<8; counter++, placeVal/=2) {
		scanf("%c", &c);
		if(c=='1')
			exponent += placeVal;
	}
	exponent = pow(2, exponent-127);
	
	// PROCESS MANTISSA: While scanning in the 23 mantissa values, if
	// a value is 1, it adds the value of that place to the mantissa
	// variable. Mantissa was initialized to 1 to accumulate correct value
	for(counter=0, placeVal=0.5; counter<23; counter++, placeVal/=2) {
		scanf("%c", &c);
		if(c=='1')
			mantissa += placeVal;
	}
	
	// Prints the result
	printf("\nThe value entered is: %g\n", sign*exponent*mantissa);
	
	return 0;
}