Example of the c ++ overload Post-auto-increment operator

The code is as follows:

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# Include <iostream> Using namespace std; Class num { Public: Int x; Num () {n = 1; cout <"constructor execution! N ";} Num (int I) {n = I; cout <": run the constructor with parameters! N ";} Num (const num & s) {this-> n = s. n; cout <"copy constructor execution! N ";} ~ Num () {cout <"destructor execution! N ";} Int get () const {return n ;} Void set (int x) {n = x ;} Void add () {++ n;} // the error code returned when the custom addition function is incorrect: expected '; 'before': 'toke Const num & operator ++ () {// pre-auto-increment. The key to const is to prevent auto-increment after the return, that is, to avoid the appearance of ++ and so on, to avoid copying constructor calls by referencing '&', operator is the c ++ keyword function name, which is the same as the normal number of reloads. The type of the c ++ defined operator, the following ++ indicates that the auto-increment operator is reloaded, and the implementation part is in {}. ++ N; Return * this; // * shis is the original object } Const num operator ++ (int o) {// Post auto-addition. The Function of parameter o is different from the preceding function. The key of const is to prevent auto-addition after return, that is to say, to avoid the appearance of ++ and the like, Reference '&'. To avoid calling the copy constructor, operator is the c ++ keyword function name, which is the same as the normal number of reloads, the type of the defined operators in c ++. The following ++ indicates that the self-added operators are reloaded, and the implementation part is in {}. Num tem (* this ); This-> n ++; // this-> can be omitted Return tem; } Private: Int n; }; Int main () { Num I; // I. add (); // call the member function to implement auto-addition Num y = I ++; // Post auto-increment Cout <"I:" <I. get () <endl; // Post-auto-added I member value Cout <"y:" <y. get () <endl; // Post-auto-Added Member values of y // Y ++; this is wrong because I is an object and there is no auto-increment operation. Return 0; }