分别以直线段正三角形为初始生成元，实现迭代次数在6次以内的Kock曲线，要求用键盘交互控制迭代次数。-Equilateral triangle is a straight line segment, respectively, the initial generator, to achieve the number of iterations in less than 6 times Kock curve, requiring interaction with the keyboard controls the number of iterations.