Различные алгоритмы минимизации, реализованные в С++ / all / MDG

#include <stdio.h>
#include <math.h>
#include <conio.h>
const double e=.000001;

struct vct
{
 double x1,x2;
 vct()
 {
  x1=0;
  x2=0;
 }
 vct(double ax1,double ax2)
 {
  x1=ax1;
  x2=ax2;
 }
 const vct operator * (const double &v) const
 {
  return vct(x1*v,x2*v);
 }

 const void operator = (const vct &v)
 {
  x1=v.x1;
  x2=v.x2;
 }
 const double operator * (const vct &v) const
 {
  return (x1*v.x1+x2*v.x2);
 }

 void operator *= (const double &v)
 {
  x1*=v;
  x2*=v;
 }

 const vct operator + (const vct &v) const
 {
  return vct(x1+v.x1,x2+v.x2);
 }

 const vct operator - (const vct &v) const
 {
  return vct(x1-v.x1,x2-v.x2);
 }
};
double f(vct v)
{
 return(v.x1*v.x1+3*v.x2*v.x2+2*v.x1*v.x2);//(2*x*x+16/x);
}

double dx1(vct v)
{
 return(2*v.x1+2*v.x2);
}

double dx2(vct v)
{
 return(6*v.x2+2*v.x1);
}

double gp(vct v,vct p)
{
 vct grad;
 grad=vct(dx1(v),dx2(v));
 return(grad*p);
}

double nrm(vct z)
{
 return(sqrt(z.x1*z.x1+z.x2*z.x2));
}

void Swann4(vct& x1,double& a,double& b,vct& p)
{
 double pr;
 vct x2;
 pr=gp(x1,p);
 if(pr>0) p=vct(0,0)-p;
 b=fabs(f(x1)/pr-1);
 if(b>1) b=1;
 x2=x1+p*b;
 while(gp(x1,p)*gp(x2,p)>0)
 {
  a=b;
  b*=2;
  x1=x2;
  x2=x1+p*b;
 };
}

void main()
{
 clrscr();
 vct p,x1,x2,xc;
 double a=0,b=0,f1,f2,aa,bb,c,xx;
 x1=vct(1,1);
 p=vct(2,3);
 do
 {
  Swann4(x1,a,b,p);
   x2=x1+p*(b-a);
  do
  {
/*   f1=gp(x1,p);
   f2=gp(x2,p);
   aa=6*(f(x1)-f(x2))+3*(f1+f2);
   bb=6*(f(x2)-f(x1))-2*(2*f1-f2);
   c=f1;
   xx=(-bb+sqrt(bb*bb-4*aa*c))/(2*aa);
   xc=x1*(1-xx)+x2*xx;
/**/   xc=(x1+x2)*0.5;
   if((gp(xc,p))>0)
   {
	  x2=xc;
   }
   else
   {
	  x1=xc;
   }
  }while(nrm(x1-x2)>e*e);
   p=vct(-dx1(x1),-dx2(x1));
 }while(nrm(vct(dx1(x1),dx2(x1)))>e);
  printf("(%lg,%lg)  (%lg,%lg)",x1.x1,x1.x2,p.x1,p.x2);
// getch();
}