#include <stdio.h>

main()
{
float xa,xb,xc;
float ya,yb,yc;
float initial_delta,dx;


printf(" Xa Xc Xb 誤差 Ya Yc Yb\n");

initial_delta=1.0;
xa = 0.0;
xb = xa + initial_delta;
dx = initial_delta / 2.0;
xc = xa + dx;

ya = xa*xa*xa - 0.5;
yb = xb*xb*xb - 0.5;
yc = xc*xc*xc - 0.5;
printf("%10.7f %10.7f %10.7f %10.7f %10.7f %10.7f %10.7f\n",xa,xc,xb,dx,ya,yc,yb);
/* ----- ここから ----- */
if ( ( ya * yc ) < 0 ) {
xb = xc;
} else {
xa = xc;
}
dx /= 2.0;
xc = xa + dx;

ya = xa*xa*xa - 0.5;
yb = xb*xb*xb - 0.5;
yc = xc*xc*xc - 0.5;
printf("%10.7f %10.7f %10.7f %10.7f %10.7f %10.7f %10.7f\n",xa,xc,xb,dx,ya,yc,yb);
/* ----- ここまでをコピーする ----- */
}