Just keep adding them:
Code:
class MyClass {
public:
    MyClass() { m_iVal = 5; }
    MyClass(int iVal) { m_iVal = iVal; }

protected:
    int m_iVal;
};

void main() {
    MyClass x; // x.m_iVal = 5
    MyClass y(32); // y.m_iVal = 32
}