#include <stdio.h>
#include <math.h>


int main () {

double a;
double b, c;
double d, e, f;
double g, h, i;
double j, k, l; 
double m, n, o;
double p, q, r;
double s, t, u;
double v, w, x;
double y, z, aa;
printf("input number?");
scanf(" %lf", &a);
printf("input number?");
scanf(" %lf", &b);
printf("input number?");
scanf(" %lf", &c);
printf("input number?");
scanf(" %lf", &d);
w=a + d;
x=(a * d) - (b * c);
x=4 * x;
y=pow(w,2);
z=y - x;
aa=pow(z,.5);
g=w + aa;
g= g/2;
h=w-aa;
h=h/2; 
printf("eigenvalues are \n");
printf(" %f \n" , h);
printf(" %f \n" , g);
 i = 1 / (a - h);
 j = 1 / (a - g);
 m = i * -b;
 n = j * -b;
printf("eigenvectors are \n");
printf(" %f " , m);
printf(" %f \n" , n);
printf("100000000 100000000 \n");

}