CF #286 div 2 B. Mr. Kitayuta's Colorful Graph（dfs）

B. Mr. Kitayuta's Colorful Graph

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

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 — ai, bi (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.

Sample test(s)

input

4 51 2 11 2 22 3 12 3 32 4 331 23 41 4

output

210

input

5 71 5 12 5 13 5 14 5 11 2 22 3 23 4 251 55 12 51 51 4

output

11112

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.

题意：

求有多少种颜色的路可以从ai,到bi 。

CODE：

#include<iostream>#include<cstdio>#include<cstring>#include<cmath>#include<string>#include<algorithm>#include<cstdlib>#include<set>#include<queue>#include<stack>#include<vector>#include<map>#define N 100010#define Mod 10000007#define lson l,mid,idx<<1#define rson mid+1,r,idx<<1|1#define lc idx<<1#define rc idx<<1|1const double EPS = 1e-11;const double PI = acos ( -1.0 );const double E = 2.718281828;typedef long long ll;const int INF = 1000010;using namespace std;bool G[110][110][110];bool vis[110][110][110];int n,m,q;int s,e,ans;int flag;void dfs(int a,int x){    if(a==e)    {        ans+=1;        flag=0;        return ;    }    for(int i=1; i<=n; i++)    {        if(!flag)            break;        if(a==i)            continue;        if(G[a][i][x]&&!vis[a][i][x]&&flag)        {            vis[a][i][x]=vis[i][a][x]=1;            dfs(i,x);        }    }}int main(){    //freopen("in.txt","r",stdin);    while(cin>>n>>m)    {        memset(vis,0,sizeof vis);        memset(G,0,sizeof G);        int mm=m;        while(m--)        {            int a,b,c;            scanf("%d%d%d",&a,&b,&c);            G[a][b][c]=G[b][a][c]=1;        }        cin>>q;        while(q--)        {            scanf("%d%d\n",&s,&e);            memset(vis,0,sizeof vis);            ans=0;            for(int i=1; i<=mm; i++)            {                flag=1;                dfs(s,i);            }            printf("%d\n",ans);        }    }    return 0;}