十进制浮点数转换成IEEE754

 

 由于double精度问题，我只保留了15位小数

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

int main()
{
    double g = 0 ;
    int v = 0 ;
    int arr[100]={} ;
    int aee[100]={} ;
    double a = 0 ;//输入的实数
    scanf("%lf",&a);
    if (a > 0 ){
        v = 0 ;
     }else{
        v = 1 ;
     }
    a = fabs(a) ;
    int b = fabs(a) ;
    double c = a - b ;
    int i = 0 ;
    double f = 0 ;
    int k = 0 ;
    double p = 0 ;
    double u = 0 ;
     for ( i = 0; b > 0; i++)
    {
       arr[i] = b%2 ;
       b = b / 2 ;
    }
     for ( int j = 0; j <=i ; j++)
     {
        f=pow(10,j);
        f = f*arr[j] ;
        g = g + f ;
     }
     for (  k = 0; c>0 && k<=50 ; k++)
     {
        aee[k]= c * 2 ;
        c = c * 2 ;
        c = c - (int)c;
     }
     for ( int o = 0; o <=32 ; o++)
     {
        p =pow(0.1,o+1);
        p = p*aee[o];
        u = u + p ;
     }
     double w = u +g ;
     int s = 0 ;
     double e = w ;
     if (w > 1){
        for ( s = 0; w > 1 ; s++)
     {
        w = w /10 ;
       
     }
        w = w *10 ;

        
     }else{
        for ( s = 0; e < 1; s--)
        {
            e = e * 10 ;
        }        
     }
     int n = 0 ;
     if (w>1)
     {
       n = s -1 +127 ;
     }else{
       n = s+127 ;
     }
     
     int result[100]={} ;
     printf("%d\n",v) ;
     printf("%d\n",n) ;
     if (w>1)
     {
      printf("%.15lf\n",w) ;
     }else{
      printf("%.15lf\n",e) ;
      }
     
     
    return 0 ;
}