Task10

#define _CRT_SECURE_NO_DEPRECATE
#include "stdio.h"
#include "math.h"
#include <iostream>
using namespace std;

int a = 998;
int b = 1998;
int c = -999;
int d = -1999;
//явный метод расходится
/*double V(double Vn, double Un, double h)
{
	return (Vn*(1/h + d/2 + c*b/(2*(1/h-a/2))) + c*Un*(1/2+(1/h+a/2)/(1/h-a/2)))/(1/h-d/2+b/(2*(1/h-a/2)));
}
double U(double Vn, double Un, double h,double Vn1)
{
	return Un*(1/h+a/2)/(1/h-a/2) + b/(2*(1/h-a/2))*(Vn+Vn1);
}*/
double V(double Vn, double Un, double h)
{
	return (Vn*(1-a*h) + c*h*Un)/((1-d*h)*(1-a*h)-c*b*h*h);
}
double U(double Vn, double Un, double h,double Vn1)
{
	return (Un+b*h*Vn1)/(1-a*h);
}
void main()
{
	FILE * file = fopen("file.txt", "w");

	double u = 1.0;
	double v = 1.0;
	double prev_v;
	double h = 0.0001;

	for(int i = 1; i < 0.1/h; i++)
	{
		prev_v = v;
		v = V(v,u,h);
		u = U(prev_v,u,h,v);
		fprintf(file,"%e %e %e\n",h*i, u,v);
	}

	fclose(file);
	//getchar();
	system("pause");
	return;
}