Do not use subtraction to implement addition operations

1 int Add (int A,int  b) {2     Char * C; 3     c = (char *) A; 4     return (int) &c[b]; 5 }

According to the address to let the compiler to help you to calculate, first of a cast to address, and then find a C-headed address, the offset of the address of B, is the value of a+b.

such as a=5,b=10

C= (char*) A, at this point the address of C is 0x00000005

C[B] is the address offset sizeof (char) of C *b

Finally get C[b] address is 0x0000000f, that is, by the int cast to get 15.

Good idea

Do not use subtraction to implement addition operations