Int type is a signed integer, that is, the value of int type must be an integer, which can be a positive integer, a negative integer or zero. Its range of values varies with computer systems. Generally speaking, storing an int takes up a machine word length. Therefore, the early 16-bit IBM PC compatibles used 16 bit to store an int value, and its value range (that is, the value range of int value) was -32768 ~ 32767. At present, personal computers are generally 32 bits, so 32 bits are used to store an int value.