print ieee754(double) data

gistfile1.cpp

#include <stdio.h>
#include <tchar.h>
#include <iostream>

typedef struct {
	unsigned int fraction1: 32;
	unsigned int fraction2: 20;
	unsigned int exponent: 11;
	unsigned int sign: 1;
}field;

typedef union {
	double ex;
	field bit;
}myDouble;

void print2bin(unsigned long long val,int len){
	char ans[65];
	for(int i = len-1; i>=0; i--){
		ans[len-1-i] = ((val >> i) & 1) ? '1':'0';
	}
	ans[len]='\0';
	std::cout << ans << std::endl;
}

int _tmain(int argc, _TCHAR* argv[])
{
	myDouble data;
	unsigned long long fraction;
	int exponent;

	for(;;){
		std::cout << ">>";
		std::cin >> data.ex ;

		exponent  = (data.bit.exponent)-1023;
		fraction  = (unsigned long long)1 << 52;
		fraction += (unsigned long long)data.bit.fraction2 << 32;
		fraction += (unsigned long long)data.bit.fraction1;
		
		std::cout << "sign     =" << data.bit.sign << std::endl;
		std::cout << "exponent =" << exponent << std::endl;

		std::cout << "fraction =" << std::hex << std::showbase << fraction << std::endl;
		std::cout << "fraction =" ; print2bin(fraction,53);

		std::cout << "data     =" << std::dec<< (fraction >> (52-exponent)) << std::endl;
	}
	return 0;
}