Type Compatibilities

1. As a general rule, you cannot store value of one type in a variable of another type
   
   
2. Attempt to do so will result in reactions that can differ from one compiler to the next. Some may issue an error message, some simply give a warning message, and some may not even object at all
   
   
3. Examples of type mismatch (or mixing data types):
   
   int int_variable;
   int_variable = 2.99;
   
   Most (but not all) compilers truncates 2.99 to 2 and assign it to the integer variable int_variable
   
   int int_variable;
   double double_variable = 2.00;
   int_variable = double_variable;
   
   This last assignment statement is illegal since the value of a double variable cannot be assigned to an integer variable even when the value comes out even
   
   
4. C++ often does not check for data mismatches carefully enough, the programmer should be more careful not to abuse the language
   
   
5. If you must convert between int and float or double, then you should use the appropriate casting operators.
   If x is of type float or double, then int(x) is of type int. It is obtained from x by dropping the fractional part.
   On the other hand if x is an integer, one can use float(x) to cast it to a float, or use double(x) to cast it to a double. In either case, a decimal point and trailing zeros are added to the integer.