你能否笔尖不离纸,一笔画出下面的每个图形吗?试试看。(不走重复线路)要正确解答这道题,必须弄清一笔画图形有哪些特点。早在18世纪,瑞士的著名数学家欧拉就找到了一笔画的规律。欧拉认为,能一笔画的图形必须是连通图。连通图就是指一个图形各部分总是有边相连的,这道题中的三? Can you nib the paper and draw a picture of each one below? (Do not repeat the line) To correctly answer this question, you must make clear what features of the stroke graphics. As early as the 18th century, the famous Swiss mathematician Euler found a law of painting. Euler believes that the graph that can be drawn in one stroke must be a connected graph. Connected graphs refer to the fact that each part of a graph is always connected by edges. Three of this question?