PAT 1154 Vertex Coloring （25 分）-甲级

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 10⁴), 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

题目大意：给出一个图（先给出所有边，后给出每个点的颜色），问是否满足：所有的边的两个点的颜色不相同
分析：把所有边存起来，把所有点的颜色存起来（存的过程中放入set统计颜色个数），枚举所有边，检查是否每条边的两点个颜色是否相同，若全不相同，则输出颜色个数，否则输出No～

#include <iostream>
#include <vector>
#include <set>
using namespace std;
struct node {int t1, t2;};
int main() {
    int n, m, k;
    cin >> n >> m;
    vector<node> v(m);
    for (int i = 0; i < m; i++)
        scanf("%d %d", &v[i].t1, &v[i].t2);
    cin >> k;
    while (k--) {
        int a[10009] = {0};
        bool flag = true;
        set<int> se;
        for (int i = 0; i < n; i++) {
            scanf("%d", &a[i]);
            se.insert(a[i]);
        }
        for (int i = 0; i < m; i++) {
            if (a[v[i].t1] == a[v[i].t2]) {
                flag = false;
                break;
            }
        }
        if (flag) 
            printf("%d-coloring\n", se.size());
        else 
            printf("No\n");
    }
    return 0;
}

#include <iostream>

#include <vector>

#include <set>

using namespace std;

struct node {int t1, t2;};

int main() {

int n, m, k;

cin >> n >> m;

vector<node> v(m);

for (int i = 0; i < m; i++)

scanf("%d %d", &v[i].t1, &v[i].t2);

cin >> k;

while (k--) {

int a[10009] = {0};

bool flag = true;

set<int> se;

for (int i = 0; i < n; i++) {

scanf("%d", &a[i]);

se.insert(a[i]);

}

for (int i = 0; i < m; i++) {

if (a[v[i].t1] == a[v[i].t2]) {

flag = false;

break;

}

if (flag)

printf("%d-coloring\n", se.size());

else

printf("No\n");

}

return 0;

}

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