【单选题】【消耗次数:1】
设 G*是连通平面图 G 的对偶图, n*, m*, r* 和 n, m, r 分别为 G*和 G 的顶点数, 边数, 面数, 则下面哪个式子不正确:
n* = r;
m* = m;
r* = n - 2;
r* = n 。
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相关题目
【判断题】 设 G*是连通平面图 G 的对偶图, n*, m*, r* 和 n, m, r 分别为 G*和 G 的顶点数, 边数, 面数, 则 r* = n - 2。
①  正确
②  错误
【单选题】 设 G*是具有 k(k 3 2)个连通分支的平面图 G 的对偶图, n*, m*, r* 和 n, m, r 分别为 G*和 G 的顶点数, 边数, 面数, 则下面哪个式子不正确:
①  n* = r;
②  m* = m;
③  r* = n - k + 1;
④  r* = n 。
【多选题】 设 G*是具有 k(k 3 2)个连通分支的平面图 G 的对偶图, n*, m*, r* 和 n, m, r 分别为 G*和 G 的顶点数, 边数, 面数, 则下面哪个式子正确:
①  n* = r;
②  m* = m;
③  r* = n - k + 1;
④  r* = n 。
【多选题】 设一连通平面图G有 n个顶点, m 条边, r 个面,则下列哪些不是欧拉公式:
①  m - n + r = 2;
②  n - m - r = 2;
③  n - r + m = 2;
④  n - m + r = 2。
【单选题】 设一平面图G有 n个顶点, m 条边, r 个面,k个连通分支,则下列哪个是欧拉公式:
①  m - n + r = 2;
②  n - m + r = k + 1;
③  n - r + m = k + 1;
④  n - m + r = 2。
【多选题】 设一平面图G有 n个顶点, m 条边, r 个面,k个连通分支,则下列哪些不是欧拉公式:
①  m - n + r = 2;
②  n - m + r = k + 1;
③  n - r + m = k + 1;
④  n - m + r = 2。
【单选题】 设 G 是 n 阶自补图,则关于顶点数n 和边数 m以下哪个性质不正确:
①  2m = n(n-1)/2;
②  n = 4k, 或 n-1 = 4k, k 为正整数;
③  2m = n(n-1);
④  2m等于所以顶点度数之和。
【单选题】 设G是 n(n≥3)阶m 条边的简单平面图,则下列哪个公式是正确的:
①  m - n + r = 2;
②  m ≤ 2n - 4;
③  m ≤ 3n - 6;
④  m ≤ 4n - 8。
【单选题】 设 n 阶 m 条边的平面图是自对偶图, 则下面哪个式子正确:
①  m = 2n - 4;
②  m = 2n - 2;
③  m = 2n ;
④  m = 2n + 2 。
【单选题】 设无向图G(n, m)是连通图,则m的取值范围是( )。
①  m ≤n-1
②  m≥n-1
③  n-1≤m≤n(n-1)/2
④  m≥n(n-1)/2
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①  with
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