testowanie testów

#include <cstdio>
#include <vector>
#include <algorithm>
#include <iostream>
#include <cassert>

using namespace std;

#define f first
#define s second

const int MAXN = 2e5 + 3;

int ile[MAXN];
vector<int> v[MAXN];

void DFS(int x, int oj) {
    ile[x]++;
    for (auto it:v[x]) {
        if (it != oj)
            DFS(it, x);
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, x, y;
    string ss;
    cin >> n;
    assert(n >= 1 && n <= 200000);
    for (int i = 1; i < n; i++) {
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
        assert(x >= 1 && x <= n);
        assert(y >= 1 && y <= n);
        assert(x != y);
    }
    DFS(1, 0);
    for (int i = 1; i <= n; i++)
        assert(ile[i] == 1);
    int lng = 0;
    for (int i = 1; i <= n; i++) {
        cin >> ss;
        for (int j = 0; j < (int)(ss.size()); j++) {
            assert((int)(ss[j]) >= 'a' && (int)(ss[j]) <= 'z');
            lng++;
        }
    }
    assert(lng >= n && lng <= 1000000);
    return 0;
}