1. For each set of integers shown below, draw a simple graph(no self-loops or parallel edges) having the indicated degrees or tell why you can`t
a) 2, 2, 3, 2, 2, 3
b) 1, 1, 2, 3, 4
simple graph¸¦ ±×¸± ¼ö°¡ ¾ø´Ù.
¿Ö³ÄÇϸé, odd degreesÀÇ verticesÀÇ ¼ö°¡ evenÀÌ µÇ¾î¾ß Çϴµ¥ ±× Á¶°ÇÀ» ¸¸Á·ÇÏÁö ¾Ê´Â´Ù.
c) 1, 2, 3, 3, 5
¿ª½Ã simple graph¸¦ ±×¸± ¼ö°¡ ¾ø´Ù. ÀÌÀ¯´Â À§¿Í µ¿ÀÏÇϸç, ¸¸¾à simple graph°¡ µÇ±â À§Çؼ´Â ¸¶Áö¸· integer 5ÀÇ degree°¡ ¼º¸³Çϱâ À§Çؼ self-loop³ª parallel edge°¡ »ý°Ü¾ß¸¸ ÇÑ´Ù.
d) 1, 1, 2, 2, 4
2. Show that if self-loops and parallel edges are permitted then for any set of n, positive integers whose sum is even, there exists a graph whose n vertices have the indicated degrees
[answer] any set of positive integers =
À§ any set of positive integersÀÇ vertex¸¦ ¶ó ÇÏ°í, degree¸¦ ¶ó ÇÏÀÚ.
±×·¯¸é À§¿¡ ÇØ´çÇÏ´Â vertex¿¡ ´ëÇÑ set of¡¦(»ý·«)
3. Given an undirected, connected graph G, show that it is always possible to find a circuit which traverses each edge exactly twice, once in each direction. Show such a circuit on the graph below
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