Mr. Kitayuta's Colorful Graph

                                        Mr. Kitayuta's Colorful Graph

原题链接 http://acm.hdu.edu.cn/showproblem.php?pid=3999

Mr. Kitayuta has just bought an undirected graph consisting of n vertices and m edges. The vertices of the graph are numbered from 1 to n. Each edge, namely edge i, has a color ci, connecting vertex ai and bi.

Mr. Kitayuta wants you to process the following q queries.

In the i-th query, he gives you two integers — ui and vi.

Find the number of the colors that satisfy the following condition: the edges of that color connect vertex ui and vertex vi directly or indirectly.

Input

The first line of the input contains space-separated two integers — n and m (2 ≤ n ≤ 100, 1 ≤ m ≤ 100), denoting the number of the vertices and the number of the edges, respectively.

The next m lines contain space-separated three integers — aibi (1 ≤ ai < bi ≤ n) and ci (1 ≤ ci ≤ m). Note that there can be multiple edges between two vertices. However, there are no multiple edges of the same color between two vertices, that is, if i ≠ j, (ai, bi, ci) ≠ (aj, bj, cj).

The next line contains a integer — q (1 ≤ q ≤ 100), denoting the number of the queries.

Then follows q lines, containing space-separated two integers — ui and vi (1 ≤ ui, vi ≤ n). It is guaranteed that ui ≠ vi.

Output

For each query, print the answer in a separate line.

Examples

Input

4 5
1 2 1
1 2 2
2 3 1
2 3 3
2 4 3
3
1 2
3 4
1 4

Output

2
1
0

Input

5 7
1 5 1
2 5 1
3 5 1
4 5 1
1 2 2
2 3 2
3 4 2
5
1 5
5 1
2 5
1 5
1 4

Output

1
1
1
1
2

Note

Let's consider the first sample.

 The figure above shows the first sample.

  • Vertex 1 and vertex 2 are connected by color 1 and 2.
  • Vertex 3 and vertex 4 are connected by color 3.
  • Vertex 1 and vertex 4 are not connected by any single color.
  • 有m个颜色,在有向图中构建对点进行找祖归宗,输出联通线路的个数;
  • 开始想到的便是并查集,不过不是太熟练,样例卡了几次,做了出来,就是并查集模板,但是要变成二维数组,最后进行查询即可。
  • #include<stdio.h>
    #include<string.h>
    
    int mapp[200][200];
    
    void init()//初始化数组,为构建地图做准备
    {
        for(int i=1; i<=100; i++)
        {
            for(int j=1; j<=100; j++)
            {
                mapp[i][j]=i;
            }
        }
    }
    
    int getf(int u,int v)//路径压缩
    {
        if(mapp[u][v]==u)
        {
            return u;
        }
        else
        {
            return mapp[u][v]=getf(mapp[u][v],v);
        }
    }
    
    void merge(int u,int v,int w)//合并两子集合,找祖归宗
    {
        int t1=getf(u,w);
        int t2=getf(v,w);
        if(t1!=t2)
        {
            mapp[t1][w]=t2;
        }
    }
    
    int main()
    {
        int n,m;
        while(~scanf("%d %d",&n,&m))
        {
            init();
            int a,b,c;
            for(int i=1; i<=m; i++)
            {
                scanf("%d%d%d",&a,&b,&c);
                merge(a,b,c);
            }
            int q,u,v;
            scanf("%d",&q);//q行开始输入ui与vi
            for(int i=0; i<q; i++)
            {
                scanf("%d %d",&u,&v);
                int ans=0;
                for(int i=1; i<=m; i++)
                {
                    if(getf(u,i)==getf(v,i))//如果有祖宗相同的,便是一条联通路线
                    {
                        ans++;
                    }
                }
                printf("%d\n",ans);
            }
        }
        return 0;
    }
    
    

猜你喜欢

转载自blog.csdn.net/CambridgeICPC/article/details/81841005