CF #286 div 二 B. Mr. Kitayuta's Colorful Graph（dfs）

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

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 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.

$CF #286 div 二 B. Mr. Kitayuta's Colorful Graph（dfs）$ 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|1
const 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;
}

CF #286 div 二 B. Mr. Kitayuta's Colorful Graph（dfs）

相关推荐