jd笔试题

#include <assert.h>
#include <bits/stdc++.h>
using namespace std;
#ifndef __DEBUG__
#define dbg(...) 42
#endif
template <class T> using mpq = priority_queue<T, vector<T>, greater<T>>;

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vl = vector<ll>;
using vi = vector<int>;

int main(int argc, char **argv)
{
    int t, n, x;
    cin >> t;
    while (t--) {
        cin >> n >> x;
        vector<vector<int>> g(n + 1);
        for (int i = 1; i < n; ++i) {
            int x, y;
            cin >> x >> y;
            g[x].push_back(y), g[y].push_back(x);
        }
        vector<int> cnt(n + 1);
        function<int(int, int)> dfs = [&](int u, int fa) {
            int ret = 1;
            for (auto v : g[u]) {
                if (v == fa)
                    continue;
                // ret ^= dfs(v, u) % 2;
                ret += dfs(v, u);
            }
            return cnt[u] = ret;
        };
        dfs(x, -1);
        int xsum = 0;
        for (auto v : g[x]) {
            xsum ^= cnt[v];
        }
        bool ans = false;
        for (auto v : g[x]) {
            ans |= (cnt[v] % 2) ^ (xsum ^ cnt[v]);
        }
        // cout << (ans ? "lose" : "win") << endl;
        cout << (g[x].size() == 1 || (cnt[x] - 1) % 2 ? "win" : "lose") << endl;
    }
    return 0;
};