C + + references do left value

//reference to do left value#include <iostream>using namespacestd;intSetA (int*p) {    *p = -; return*p;}int& Setb (int*p) {    *p = -; return*p;}voidMain () {intA1 =0; //SetA (&A1) = 100; //Error C2106: "=": Left operand must be left value//SetA (&A1) operation result is a numeric value without memory address cannot be an lvalue//30=100; it's wrong .Setb (&AMP;A1) = -; printf ("a1=%d\n", A1);//print a1=100;//The essence of the previous reference shows that SETB (&A1) Returns a reference pointer//the C + + compiler will perform a pick-up operation by default when a reference is made to the left value//namely *p=100; This is a syntax-compliantSystem"Pause");}

C + + references do left value