The real type is actually a floating-point number, which is divided into single-precision floating-point number and double-precision floating-point number, which are 32 bits and 64 bits long respectively. Represents different ranges of numbers.
The character type is an 8-bit integer. If it is an unsigned character type, it can only represent positive integers between 0 and 255. Signed integer, which can represent positive and negative integers between-128 and 127. ASCII characters can be represented by character types.
Integer variable is a computer language. In C language, the values of integer variables can be decimal, octal and hexadecimal, but binary numbers are stored in memory. Variables, as the name implies, are variables whose values can be changed, and integer variables represent integer data.
Real variables whose values can be changed in the process of program running are called real variables, which are divided into single precision (float), double precision (double) and long double precision (long double).
Character quantity includes character constant and character variable. A string constant is a sequence of characters enclosed in a pair of double quotes. The value of a character variable is a character constant, that is, a single character. The type specifier of a character variable is char. The format and writing rules of type description of character variables are the same as those of integer variables.
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Integer variable-Baidu Encyclopedia? Real change-Baidu encyclopedia? Number of people-Baidu Encyclopedia