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1. Type conversion

  
 

   
  

  
 bool b = 42; // _b is true_
   
  

  
int i = b; // _i has value 1_
   
  

  
i = 3.14; // _i has value 3_
   
  

  
double pi = i; // _pi has value 3.0_
   
  

  
unsigned char c = -1; // _assuming 8-bit chars_, _c has value 255_
   
  

  
signed char c2 = 256; // _assuming 8-bit chars_, _the value of c2 is__undefined_
  
 

The range of values that a type can represent determines the process of conversion:

• When we assign an arithmetic value of a non-Boolean type to a Boolean type, the initial value is 0 and the result is false,
  Otherwise, the result is true.
• When we assign a Boolean value to a non-Boolean type, the initial value is false and the result is O, and the initial value is
  True, the result is 1.
• When we assign a floating-point number to an integer type, the approximation is processed. The resulting value will retain only the floating-point
  The part before the decimal point.
• When we assign an integer value to a floating-point type, the fractional part is recorded as 0. If the integer occupies a space that is super-
  There may be a loss of precision over the capacity of floating-point types.
• When we assign an unsigned type to a value that exceeds the range it represents, the result is an initial value pair of unsigned type table
  Shows the remainder of the total number of values after modulo. For example, a 8-bit-size unsigned char can represent a value within a range of 0 to 255, and if we assign a value other than an interval, the actual result is the remainder of the value on 256 modulo. Therefore, the result of assigning 1 to a 8-bit size unsigned char is 255.
• The result is undefined (undefined) when we assign a symbol type and a value that exceeds the range it represents.
  At this point the process may continue to Guiren, may crash, or may generate garbage data.

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