[编程入门]自定义函数求一元二次方程 C++

# include <iostream>
# include<iomanip>
# include<cmath>
using namespace std;
int main()
{
    int a,b,c;
    double delt,x1,x2;
    cin>>a>>b>>c;
    delt=b*b-4*a*c;
    if(delt<0)
          cout<<fixed<<setprecision(3)<<"x1="<<(-b*1.0)/2/a<<"+"<<sqrt(-delt)/2/a<<"i"<<'\t'<<"x2="<<(-b*1.0)/2/a<<"-"<<sqrt(-delt)/2/a<<"i"         <<endl;
   else
   {
      if(delt==0)
              cout<<fixed<<setprecision(3)<<"x1="<<-b/2/a<<'\t'<<"x2="<<-b/2/a<<endl;
      else
               cout<<fixed<<setprecision(3)<<"x1="<<(-b+sqrt(delt))/2/a<<'\t'<<"x2="<<(-b-sqrt(delt))/2/a<<endl;
    }
    return 0;
}