Помогите с задачей - C++ - Ответ 2166357

//Программа для решения задач квадратных уравнении
#include <iostream>
#include <cmath>
#include <cstdlib>
using namespace std;
int main()
{
    int a,b,c,D;
    cout<<"Now we choose a square of the equation!\n"<<"Please enter \"a\": ";
    cin>>a;
    cout<<endl<<"Please enter \"b\": ";
    cin>>b;
    cout<<endl<<"Please enter \"c\": ";
    cin>>c;
    D=sqr(a)-4*a*c;
        if (a==0)
            cout<<"X does not have a solution!"<<endl; //X не имеет решения!
        else if (a=1 & b=1)
            cout<<"Your square of the equation is: "<<"X^2+X+"<<c<<"=0"<<endl;
        else if (b=1)
            cout<<"Your square of the equation is: "<<"a*(X^2)+X+"<<c<<"=0"<<endl;
        else if (a=1)
            cout<<"Your square of the equation is: "<<"X^2+b*X+"<<c<<"=0"<<endl;
        else
            cout<<"Your square of the equation is: "<<"a*(X^2)+b*X+"<<c<<"=0"<<endl;
        cout<<"D=a^2-4*a*c="<<sqr(a)"-("<<4*a*c")="<<sqr(a)-4*a*c<<endl;
        if (D<0)
            cout<<"The square of the equation has no solution"<<endl;
        else if (D=0)
            cout<<"--------------------"<<"X=(-b)/(2*a)="<<(-b)/(2*a)<<endl;
        else {cout<<"--------------------"<<"X1=(-b)+sqrt(D)/(2*a)="<<(-b)+sqrt(D)/(2*a)<<endl;
        cout<<"X2=(-b)-sqrt(D)/(2*a)="<<(-b)-sqrt(D)/(2*a)<<endl;}
        cout<<"Thanks, that solved the problem with me! :)";
        return (0);
}