Why is *p++ different from *p += 1?

Question

Consider:

void foo1(char **p) { *p++; }
void foo2(char **p) { *p += 1; }

and

char *s = \"abcd\";
char *a = s; 
foo1(&a)         


        

Answer 1

Precedence of prefix ++ and * is same. Associativity of both is right to left. Precedence of postfix ++ is higher than both * and prefix ++. Associativity of postfix ++ is left to right.