Automatic conversion of parameter symbols during C language operations

A simple question? In C, which of the int and unsigned int have a large value range? Note that the value 0 contains + 0 and-0 in the int, and the value 0 in the unsigned int has only one + 0, so the value range of the unsigned int is greater than that of the int. The C language operation code is as follows: # include <stdio. h> int main (int argc, char ** argv) {int val =-15; unsigned int value = 13; int sum = value + val; printf ("sum % d \ n", sum); return 0;} What is the sum result above? Think for the answer to this question. In the C language formula, if there are different types of variables, variables with a small value range will be automatically converted to the type of variables with a large value range. Therefore, the C language conversion rules are: variables such as www.2cto.com 1 char and short will be automatically upgraded to int type variables 2 unsigned char and unsigned short variables will be automatically upgraded to unsigned int type variables 3 There are unsigned and signed type variables, the type of a variable with a small value range will be upgraded to the type of a variable with a large value range. According to the third rule above, the val operation type in the above Code is unsigned int. Many other so-called rules can be easily deduced using the third rule.