How to output x++ with operator++ in class? [duplicate]

How to output x++ with operator++ in my class CTimeSpan. I create like the following example:

#include <iostream>
using namespace std;
class CTimeSpan {
private:
    unsigned int day; //day
    unsigned int hour;
    unsigned int minute;
    unsigned int second;

public:
    ostream& operator<<(ostream& os,const CTimeSpan& tm)
    {
        os << tm.day << "d"
           << " " << tm.hour << "h"
           << " " << tm.minute << "p"
           << " " << tm.second << "s";
        return os;
    }
    CTimeSpan CTimeSpan::operator++(int s) {
            CTimeSpan temp = *this;
            ++* this;
            return temp;
     }
};
int main()
{
    CTimeSpan tm1{ 1, 2, 3, 4 };
    cout << tm1++; //it's error "<<"
}

*thank you very much. Help me