#include<bits/stdc++.h>
#define pb emplace_back
using namespace std;
using ll = long long;
const int maxn = 40001;
const int bs = maxn;
//const int bs = 10;
int n, k;
vector<int> edge[maxn];
bitset<bs> dp[2][maxn];
int sz[maxn];
void add(int& a, int v) {
    a += v-k;
    a += (a>>31)&k;
}
void gs(int now, int last = 0) {
    sz[now] = 1;
    if (auto it = find(edge[now].begin(), edge[now].end(), last); it != edge[now].end()) {
        swap(*it, edge[now].back());
        edge[now].pop_back();
    }
    for (int u : edge[now])
        gs(u, now), add(sz[now], sz[u]);
}
bool ans[maxn];
void dfs(int now) {
    static int d;
    add(d, 1);
#define cd d
    //int cd = d;
    ans[now] = (!cd || (((dp[0][now] << cd) | (dp[0][now] >> (k-cd))) & (dp[1][now])).any());
    //ans[now] = (dp[0][now] & dp[1][now])[ k - cd ];
    auto &e = edge[now];
    if (e.size()) {
#define GL(u) (sz[u] ? dp[0][u] | (dp[0][u] << sz[u]) | (dp[0][u] >> (k-sz[u])) : dp[0][u])
#define GR(u) (sz[u] ? dp[1][u] | (dp[1][u] >> sz[u]) | (dp[1][u] << (k-sz[u])) : dp[1][u]);
        dp[0][ e[0] ] = dp[0][now];
        dp[1][ e.back()] = dp[1][now];
        for (int i = 0;i+1 < e.size();++i)
            dp[0][e[i+1]] = GL(e[i]);
        for (int i = e.size()-1;i > 0;--i)
            dp[1][e[i-1]] = GR(e[i]);

        for (int u : edge[now])
            dfs(u);
    }
    --d;
    d += (d>>31)&k;
}
signed main(){
    ios_base::sync_with_stdio(0), cin.tie(0);
    cin >> n >> k;
    for (int i = 1, a, b;i < n;++i) {
        cin >> a >> b;
        edge[a].pb(b);
        edge[b].pb(a);
    }
    dp[0][1][k] = dp[0][1][0] = dp[1][1][0] = dp[1][1][k] = true;
    gs(1);
    dfs(1);
    for (int i = 1;i <= n;++i)
        cout << (ans[i]?'Y':'N');
    cout << '\n';
}