1154 Vertex Coloring (25分)
A proper vertex coloring is a labeling of the graph's vertices with colors such that no two vertices sharing the same edge have the same color. A coloring using at most k colors is called a (proper) k-coloring.
Now you are supposed to tell if a given coloring is a proper k-coloring.
Input Specification:
Each input file contains one test case. For each case, the first line gives two positive integers N and M (both no more than 1), being the total numbers of vertices and edges, respectively. Then M lines follow, each describes an edge by giving the indices (from 0 to N−1) of the two ends of the edge.
After the graph, a positive integer K (≤ 100) is given, which is the number of colorings you are supposed to check. Then K lines follow, each contains N colors which are represented by non-negative integers in the range of int. The i-th color is the color of the i-th vertex.
Output Specification:
For each coloring, print in a line k-coloring
if it is a proper k
-coloring for some positive k
, or No
if not.
Sample Input:
10 11
8 7
6 8
4 5
8 4
8 1
1 2
1 4
9 8
9 1
1 0
2 4
4
0 1 0 1 4 1 0 1 3 0
0 1 0 1 4 1 0 1 0 0
8 1 0 1 4 1 0 5 3 0
1 2 3 4 5 6 7 8 8 9
Sample Output:
4-coloring
No
6-coloring
No
图着色问题,我们已知图,如果每相邻两个节点都着色不一样,则打印一共有多少种颜色,否则打印No
#include <iostream> #include <vector> #include <map> using namespace std; int N, M, K; int main() { scanf("%d%d", &N, &M); vector<pair<int, int>> v(M); for(int i = 0; i < M; i++) scanf("%d%d", &v[i].first, &v[i].second); scanf("%d", &K); vector<int> color(N); while(K--) { map<int, bool> m; for(int i = 0; i < N; i++) { scanf("%d", &color[i]); m[color[i]] = true; } bool isRight = true; for(int i = 0; i < M; i++) { if(color[v[i].first] == color[v[i].second]) { isRight = false; break; } } if(isRight) printf("%lu-coloring\n", m.size()); else printf("No\n"); } return 0; }