Consider the below C++ program and predict the output. CPP

   #include          using     namespace     std  ;   int     main  ()   {      float     f     =     0xffffffff  ;      unsigned     int     x     =     0xffffffff  ;     // Value 4294967295      if     (  f     ==     x  )         cout      < <     'true'  ;      else         cout      < <     'false'  ;      return     0  ;   }   

The output of above program is lažno ako ' IEEE754 32-bitni single float tip ' is used by compiler. If we define: CPP

   float     f     =     0xffffffff  ;   

We are basically trying to assign a 32-bit integer (signed or unsigned) to a 32-bit float. The compiler will first convert the integer 0xffffffff to a nearest 32-bit float and the memory representation of the float f is not the same as the integer 0xffffffff. We can see the above values by printing f and x. CPP

   #include          using     namespace     std  ;   int     main  ()   {      float     f     =     0xffffffff  ;      unsigned     int     x     =     0xffffffff  ;         cout      < <     'f = '      < <     f      < <     endl  ;      cout      < <     'x = '      < <     x      < <     endl  ;      return     0  ;   }   

Output :

f = 4.29497e+09 x = 4294967295  

Even if we copy the memory directly for example we have an integer (value equal to 0xffffffff) and we copy over the content (memory values). Since the 0xffffffff in IEEE754 is not a valid float number so if you compare this invalid representation to itself it is not equal. CPP

   unsigned     int     x     =     0xffffffff  ;   memoryCopy  (  &  f       &  x       sizeof  (  x  ));   

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