题目地址

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 10
​4
​​ ), 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

#include<iostream>
#include<algorithm>
#include<string>
#include<math.h>
#include<map>
#include<vector>
using namespace std;
const int maxn=10010;
int n,m,k;
vector<int>v[maxn];
int main(){
    cin>>n>>m;int v1,v2;
    for(int i=0;i<m;i++){
        cin>>v1>>v2;
        v[v1].push_back(v2);
//        v[v2].push_back(v1);
    }
    cin>>k;
    while(k--){
        int w[maxn]={0};bool flag=1;int cnt=0;map<int,bool>book;        //真见呢，又是这个坑，看见段错误就像换map；
        for(int i=0;i<n;i++) {
            cin>>w[i];
            if(!book[w[i]]){
                cnt++;book[w[i]]=1;
            }
        }
        for(int i=0;i<n;i++){
            if(!flag) break;
            for(int j=0;j<v[i].size();j++){
                if(w[i]==w[v[i][j]]){
                    flag=0;break;
                }
            }
        }
        if(flag) cout<<cnt<<"-coloring"<<endl;
        else cout<<"No"<<endl;
    }
    return 0;
}