czj/VS Code/fangcheng.cpp

#include <iostream>
#include <math.h>
using namespace std;
int main()
{
    double a,b,c,a2,a21,b1,x1,x2,gdelta,delta1,mum,den,mum1,den1;
    int qu=1,delta,delta2;
    cout<<"请输入a、b、c"<<endl;
	cin>>a>>b>>c;//输入系数
    cout<<a<<"x^2+"<<b<<"x+"<<c<<"=0"<<endl;
	delta=delta1=(b*b)-(4*a*c); 
    cout<<"delta="<<delta<<endl;
    if (delta>=0&&(b*b)-(4*a*c)==floor((b*b)-(4*a*c)))//判断Δ是否>=0以及是否是整数
    {
        gdelta=sqrt(delta);
        if (gdelta==floor(gdelta))//判断根号下Δ是否是整数
        {
            x1=(-b+gdelta)/(2*a);
            x2=(-b-gdelta)/(2*a);
            if (x1==floor(x1)&&x2==floor(x2))//判断解是不是整数
            {
                cout<<"x1="<<x1<<"\nx2="<<x2<<endl;
            }
            else
            {
                mum=-b+gdelta;
                den=2*a;
                for (int j = 2; j<=fabs(mum)&&j<=fabs(den); j++)
                {
                    mum1=mum/j;
                    den1=den/j;
                    if (mum1==floor(mum1)&&den1==floor(den1))
                    {
                        mum=mum1;den=den1;
                        j=j-1;
                    }
                }
                cout<<"x1="<<mum<<"/"<<den<<endl;
                mum=-b-gdelta;
                den=2*a;
                for (int j = 2; j<=fabs(mum)&&j<=fabs(den); j++)
                {
                    mum1=mum/j;
                    den1=den/j;
                    if (mum1==floor(mum1)&&den1==floor(den1))
                    {
                        mum=mum1;den=den1;
                        j=j-1;
                    }
                }
                cout<<"x2="<<mum<<"/"<<den<<endl;
            }
        }
        else
        {
            delta2=delta;
            for(int i=2;i<=delta;i++)
            {
                int cnt=0;
                while(delta!=i)
                {
                    if(delta%i==0)
                    {
                        cnt++;
                        delta=delta/i;
                        delta2=delta2/i;
                    }
                    else break;
                }
                if(i==delta)
                {
                    cnt++;
                    delta=delta/i;
                    delta2=delta2/i;
                }
                if(cnt!=0)
                {
                    if (cnt%2==0)
                    {
                        qu=qu*pow(i,cnt/2);
                    }
                    if (cnt%2!=0)
                    {
                        qu=qu*pow(i,(cnt-1)/2);
                        delta2=delta2*i;
                    }
                }
            }//开根号
            a2=2*a;
            for (int j = 2; j<=fabs(a2)&&j<=fabs(b)&&j<=fabs(qu); j++)
            {
                a21=a2/j;
                b1=b/j;
                if (qu%j==0&&b1==floor(b1)&&a21==floor(a21))
                {
                    qu=qu/j;a2=a21;b=b1;
                    j=j-1;
                }
            }//化简
            cout<<"x1=("<<-b<<"+"<<qu<<"*sqrt("<<delta2<<"))/"<<a2<<"\nx2=("<<-b<<"-"<<qu<<"*sqrt("<<delta2<<"))/"<<a2<<endl;
        }
    }
    else if (delta>=0)
    {
        gdelta=sqrt(delta1);
        cout<<"delta="<<delta1<<endl;
        x1=(-b+gdelta)/(2*a);
        x2=(-b-gdelta)/(2*a);
        cout<<"x1="<<x1<<"\nx2="<<x2<<endl;
    }//如果Δ是小数的话，暴力求解（本人技术有限）
    else
    {
        cout<<"方程无实数根"<<endl;
    }
    system("pause");
    return 0;
}