#include "pssub.h"

void main()
{    
     init();
     viewport(0.2,0.2,0.8,0.8); xyworld(0.0,0.0,1.0,1.0);
     linety(2); rect(0.0, 0.0, 1.0, 1.0);stroke();
     newpath(); plot(0.1, 0.1, 3); plot(0.5, 0.1, 2); 
                plot(0.5, 0.4, 2); plot(0.9, 0.4, 2); stroke();
                circ(0.1, 0.1, 0.004); fill(); 
                circ(0.5, 0.1, 0.004); fill();
                circ(0.5, 0.4, 0.004); fill();
                circ(0.9, 0.4, 0.004); fill();
     linety(1); linewidth(2.0); 
     newpath(); plot(0.1, 0.1, 3); curvto(0.5,0.1,0.5,0.4,0.9,0.4); 
     stroke();
     text(0.06,0.04,"(0.1,0.1)");  text(0.52,0.04,"(0.5,0.1)"); 
     text(0.42,0.45,"(0.5,0.4)");  text(0.82,0.45,"(0.9,0.4)"); 
     stroke();
     fin(); 
}