#include<iostream>
/* defining ordinary differential equation to be solved */
/* In this example we are solving dy/dx = x + y */
#define f(x,y) x+y
using namespace std;
int main()
{
float x0, y0, xn, h, yn, slope;
int i, n;
cout<<"Enter Initial Condition"<< endl;
cout<<"x0 = ";
cin>> x0;
cout<<"y0 = ";
cin >> y0;
cout<<"Enter calculation point xn = ";
cin>>xn;
cout<<"Enter number of steps: ";
cin>> n;
/* Calculating step size (h) */
h = (xn-x0)/n;
/* Euler's Method */
cout<<"\nx0\ty0\tslope\tyn\n";
cout<<"------------------------------\n";
for(i=0; i < n; i++)
{
slope = f(x0, y0);
yn = y0 + h * slope;
cout<< x0<<"\t"<< y0<<"\t"<< slope<<"\t"<< yn<< endl;
y0 = yn;
x0 = x0+h;
}
/* Displaying result */
cout<<"\nValue of y at x = "<< xn<< " is " << yn;
return 0;
}
/*
For output
Enter Initial Condition
x0 = 0
y0 = 1
Enter calculation point xn = 0.5
Enter number of steps: 10
*/
