Int is integer data, such as: int a, then the value of a can only be an integer; For example, a=3.
Char is a character type, such as: char a, then the value of a can only be a character type; For example, a='a'.
Float is floating-point data, such as: float a, then the value of a can only be floating-point data; For example, a = 3.50& lt is the real number in our mathematics: it must be written in decimal >; .
2. Different memory sizes
The memory size of int is 4 bytes.
The memory size of char is 1 byte.
The size of floating-point memory is 4 bytes.
3, indicating the data range.
Int: The range of numbers is -(3 1 of 2-1) to (3 1 of 2-1), and the number is-2147 483 647 ~ 2147 47.
char:- 128- 127 .
Float: integer limit is 3.4 * 10 38, and so is negative number.
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