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Atribuindo um número inteiro para flutuar e comparação em C/C++

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 falso se o ' Tipo flutuante único IEEE754 de 32 bits ' 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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