为什么这里打印的复数不正确?

我正在尝试完成使用复数运算的 c++ 赋值代码。我在操作中使用的逻辑几乎没问题，但我无法让输出按照我想要的方式出来。这一定是一个逻辑错误，但我只是不明白。

我已经尝试了构造函数，参数化等，但我只是没有得到它。

#include<iostream>
using namespace std;
class complex
{
int r, i;
public:
int Read()
{
cout << "Enter Real part" << endl;
cin >> r;
cout << "Enter Imaginary part" << endl;
cin >> i;
return 0;
}
complex Add(complex A, complex B)
{
complex sum;
sum.r = A.r + B.r;
sum.i = A.i + B.i;
return sum;
}
complex Subtract(complex A, complex B)
{
complex diff;
diff.r = A.r - B.r;
diff.i = A.i - B.i;
return diff;
}
complex Multiply(complex A, complex B)
{
complex prod;
prod.r = A.r*B.r + A.i*B.i*(-1);
prod.i = A.r*B.i + B.r*A.i;
return prod;
}
complex Divide(complex A, complex B)
{
complex c_B; //conjugate of complex number B
c_B.r = B.r;
c_B.i = -B.i;
complex quotient;
complex numerator;
complex denominator;
numerator.Multiply(A, c_B);
denominator.Multiply(B, c_B);
int commonDenom = denominator.r + denominator.i;
quotient.r = numerator.r / commonDenom;
quotient.i = numerator.i / commonDenom;
return quotient;
}
int Display()
{
cout << r << "+" << i << "i" << endl;
return 0;
}
};
int main()
{
complex a, b, c;
cout << "Enter first complex number" << endl;
a.Read();
cout << "Enter second complex number" << endl;
b.Read();
c.Add(a, b);
c.Display();
c.Multiply(a, b);
c.Display();

system("pause");
return 0;
}


the expected output on input of 1+2i and 2+3i should be
3+5i
8+i
but output is
-858993460+-858993460i
-858993460+-858993460i