#include <iostream>

using namespace std;

class cnumber {
	private:
		int r, i;
		bool signr, signi;
		bool get_sign(int i) {
			return (i >= 0);
		}

	public:
		cnumber(int a, int b) {
			r = a;
			i = b;
			signr = get_sign(r);
			signi = get_sign(i);
			
		}
		cnumber operator+(const cnumber &that) {
			cnumber z(that.r + this->r, that.i + this->i);
			return z;
		}
		cnumber operator*(const cnumber &that) {
			cnumber z( (that.r * this->r ) - (that.i * this->i) , (that.r * this->i) + (this->r * that.i) );
			return z;
		}

		friend ostream &operator<<( ostream &os, const cnumber &z ) { 
			os << z.r << (z.signi ? '+' : '\0' ) <<  z.i << 'i'; 
			return os;            
		}


};