录制文件：https://meeting.tencent.com/crm/KEO4gwE7d7

#include<bits/stdc++.h>
using namespace std;
const int  N = 1e5 + 9;
struct node{
    int x, y, w;
}e[N];
int n, m;
struct nn{
    int y, w;
};
vector<nn> g[N];
bool cmp(node a, node b){
    return a.w > b.w;
}
int f[N], cnt;
int find(int x){
    return f[x] == x ? x : f[x] = find(f[x]);
}

void merge(int x, int y){
    int fx = find(x);
    int fy = find(y);
    if(fx!=fy)
        f[fx] = fy;
}
int dep[N], fa[N][22], mn[N][22];
int kur(){
    sort(e + 1, e + m + 1, cmp);
    int ans = 0;
    for(int i = 1; i <= m; i++){
        int x = e[i].x, y = e[i].y, w = e[i].w;
        if(find(x) == find(y)) continue;
        g[x].push_back({y, w});
        g[y].push_back({x, w});
        merge(x, y);
        cnt++;
        if(cnt==n-1)break;
    }
    return ans;
}
void dfs(int x, int _fa, int w){
    dep[x] = dep[_fa] + 1;
    fa[x][0] =  _fa;
    mn[x][0] = w; //x -> _fa 的权值
    for(int i = 1; i <= 19; i++){
        fa[x][i] = fa[fa[x][i-1]][i-1];
        mn[x][i] = min(mn[fa[x][i-1]][i-1], mn[x][i-1]);
    }
    for(int i = 0; i < g[x].size(); i++){
        int y = g[x][i].y, w = g[x][i].w;
        if(y == _fa) continue;
        dfs(y, x, w);
    }
}

int lca(int x, int y){
    if(dep[x] < dep[y]) swap(x, y);
    int d = dep[x] - dep[y];
    int ans = 0x3f3f3f3f;
    for(int i = 19; i >= 0; i--){
        if((1<<i) & d) {
            ans = min(ans, mn[x][i]);
            x = fa[x][i];
        }
    }
    if(x == y) return ans;
    for(int i = 19; i >= 0; i--){
        if(fa[x][i] != fa[y][i]){
            ans=min({ans, mn[x][i], mn[y][i]});
            x = fa[x][i], y = fa[y][i];
        }
    }
    ans = min({ans, mn[x][0], mn[y][0]});
    return ans;
}


int main(){
    cin >> n >> m;
    for(int i = 1; i <= n; i++)
        f[i] = i;
    for(int i = 1; i <= m; i++){
        int x, y, w;
        cin >> x >> y >> w;
        e[i] = {x, y, w};
    }
    memset(mn, 0x3f, sizeof mn);
    kur();
    for(int i = 1; i <= n; i++){
        // cout << fa[i] << " ";
        if(fa[i][0] == 0){
            // cout << i << "::::\n";
            dfs(i, 0, 0);
        }
    }
    // cout << "###" << fa[5][0] << "\n";
    cin >> m;
    while(m--){
        int x, y;
        cin >> x >> y;
        if(find(x) != find(y)) {
            puts("-1");
            continue;
        }
        cout << lca(x, y) << "\n";
    }
    return 0;
}