function  shape_display(num)

fid=fopen(strcat('50_points\',int2str(num),'.pnt'),'r');

tmp=fscanf(fid,'%d');

for i=1:size(tmp,1)/2
    point_x(i)=tmp(i*2-1);
    point_y(i)=tmp(i*2);
end
fclose(fid);

figure,plot(point_x,point_y);