ForAlisa

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define X first
#define Y second
#define ll long long
#define pii pair<int, int>
using namespace std;

struct node{
    int p, c, num;
    vector<int> g;
};

node nodes[50005];
int n, up[50005][20], x, y, tin[50005], ts, minr[50005][20], l, tout[50005], m;

void dfs(int vi, int p = 1){
    node v = nodes[vi];
    tin[vi] = ++ts;
    up[vi][0] = p;
    if(vi == 1){
        for(int i = 0; i <= l; ++i){
            minr[1][i] = 1e9;
        }
    }
    else{
        minr[vi][0] = v.c;
    }
    for(int i = 1; i <= l; ++i){
        up[vi][i] = up[up[vi][i - 1]][i - 1];
        minr[vi][i] = min(minr[vi][i - 1], minr[up[vi][i - 1]][i - 1]);
    }
    for(int i = 0; i < (int)v.g.size(); ++i){
        int to = nodes[v.g[i]].num;
        if(to != p){
            dfs(to, vi);
        }
    }
    tout[vi] = ++ts;
}

bool upper(int a, int b){
    return tin[b] >= tin[a] && tout[b] <= tout[a];
}

int lca(int a, int b){
    if(upper(a, b)) return a;
    if(upper(b, a)) return b;
    for(int i = l; i >= 0; --i){
        if(!upper(up[a][i], b)){
            a = up[a][i];
        }
    }
    return up[a][0];
}

int getmin(int p, int s){
    if(p == s){
        return 1e9;
    }
    int minv = 1e9;
    for(int i = l; i >= 0; --i){
        if(!upper(up[s][i], p)){
            minv = min(minv, minr[s][i]);
            s = up[s][i];
        }
    }
    return min(minv, minr[s][0]);
}

int ask(int a, int b){
    int m;
    m = lca(a, b);
    return min(getmin(m, a), getmin(m, b));
}

int main(){
    #ifdef DEBUG
       freopen("input.txt", "r", stdin);
    #endif // DEBUG
    freopen("minonpath.in", "r", stdin);
    freopen("minonpath.out", "w", stdout);
    ts = 0;
    cin >> n;
    nodes[1].p = -1;
    nodes[1].c = 1e9;
    nodes[1].num = 1;
    for(int i = 2; i <= n; ++i){
        cin >> x >> y;
        nodes[i].p = x;
        nodes[i].c = y;
        nodes[i].num = i;
        nodes[x].g.pb(i);
    }
    l = 1;
    while((1 << l) <= n) ++l;
    dfs(1);
    cin >> m;
    for(int i = 1; i <= m; ++i){
        cin >> x >> y;
        cout << ask(x, y) << endl;
    }
    return 0;
}