a+++b

#include <iostream>
#include "strange_plus.h"
using namespace std;

int main() {
    integer a, b;
    int t1, t2, ans;
    t1 = a + b;
    t2 = ++a;
    cout << t1 << endl;
    cout << t2 << endl;
    ans = a+(++b);
    cout << ans << endl;
    return 0;
}

#include <string.h>

class integer {
  public:
    integer() {
        data = 1;
    }
    ~integer() {}
    
    friend int operator + (const integer i1, const integer i2) {
        int temp1 = i1.data;
        int temp2 = i2.data;
        int temp3 = 0;
        int ans = 0;
        while (temp1 || temp2) {
            temp3 = temp3 * 10 + ((temp1 % 10 + temp2 % 10) % 10);
            temp1 /= 10;
            temp2 /= 10;
        }
        while (temp3) {
            ans = ans * 10 + temp3 % 10;
            temp3 /= 10;
        }
        return ans;
    }
    
    int operator ++ () {
        int temp[10];
        memset(temp, 0, sizeof(temp));
        int temp_int = data;
        int i = 0;
        while (temp_int) {
            temp[i++] = temp_int % 10;
            temp_int /= 10;
        }
        for (int j = 0; j < i; j++) {
            temp[j] = (temp[j] + 1) % 10;
        }
        int ans = 0;
        for (int j = i - 1; j >= 0; j--) {
            ans = ans * 10 + temp[j];
        }
        data = ans;
        return ans;
    }
    
  private:
    int data;
};