Problem:
Score : 100 points

Problem Statement

Consider placing N flags on a line. Flags are numbered through 1 to N.

Flag i can be placed on the coordinate X_i or Y_i.
For any two different flags, the distance between them should be at least D.

Decide whether it is possible to place all N flags. If it is possible, print such a configulation.

Constraints

1 \leq N \leq 1000

0 \leq D \leq 10^9

0 \leq X_i < Y_i \leq 10^9

All values in Input are integer.

Input

Input is given from Standard Input in the following format:

N D
X_1 Y_1
X_2 Y_2
\vdots
X_N Y_N

Output

Print No if it is impossible to place N flags.

If it is possible, print Yes first.
After that, print N lines. i-th line of them should contain the coodinate of flag i.

Sample Input 1

3 2
1 4
2 5
0 6

Sample Output 1

Yes
4
2
0

Sample Input 2

3 3
1 4
2 5
0 6

Sample Output 2

No

Solution in C++ (GCC 9.2.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

template <class E> struct csr {
    std::vector<int> start;
    std::vector<E> elist;
    csr(int n, const std::vector<std::pair<int, E>>& edges) : start(n + 1), elist(edges.size()) {
        for (auto e : edges) {
            start[e.first + 1]++;
        }
        for (int i = 1; i <= n; i++) {
            start[i] += start[i - 1];
        }
        auto counter = start;
        for (auto e : edges) {
            elist[counter[e.first]++] = e.second;
        }
    }
};
struct scc_graph {
public:
    scc_graph(int n) : _n(n) {}

    int num_vertices() { return _n; }
 
    void add_edge(int from, int to) { edges.push_back({ from, {to} }); }
 
    // @return pair of (# of scc, scc id)
    std::pair<int, std::vector<int>> scc_ids() {
        auto g = csr<edge>(_n, edges);
        int now_ord = 0, group_num = 0;
        std::vector<int> visited, low(_n), ord(_n, -1), ids(_n);
        visited.reserve(_n);
        auto dfs = [&](auto self, int v) -> void {
            low[v] = ord[v] = now_ord++;
            visited.push_back(v);
            for (int i = g.start[v]; i < g.start[v + 1]; i++) {
                auto to = g.elist[i].to;
                if (ord[to] == -1) {
                    self(self, to);
                    low[v] = std::min(low[v], low[to]);
                }
                else {
                    low[v] = std::min(low[v], ord[to]);
                }
            }
            if (low[v] == ord[v]) {
                while (true) {
                    int u = visited.back();
                    visited.pop_back();
                    ord[u] = _n;
                    ids[u] = group_num;
                    if (u == v) break;
                }
                group_num++;
            }
        };
        for (int i = 0; i < _n; i++) {
            if (ord[i] == -1) dfs(dfs, i);
        }
        for (auto& x : ids) {
            x = group_num - 1 - x;
        }
        return { group_num, ids };
    }
 
    std::vector<std::vector<int>> scc() {
        auto ids = scc_ids();
        int group_num = ids.first;
        std::vector<int> counts(group_num);
        for (auto x : ids.second) counts[x]++;
        std::vector<std::vector<int>> groups(ids.first);
        for (int i = 0; i < group_num; i++) {
            groups[i].reserve(counts[i]);
        }
        for (int i = 0; i < _n; i++) {
            groups[ids.second[i]].push_back(i);
        }
        return groups;
    }
private:
    int _n;
    struct edge {
        int to;
    };
    std::vector<std::pair<int, edge>> edges;
};
struct two_sat {
public:
    two_sat() : _n(0), scc(0) {}
    two_sat(int n) : _n(n), _answer(n), scc(2 * n) {}
 
    void add_clause(int i, bool f, int j, bool g) {
        assert(0 <= i && i < _n);
        assert(0 <= j && j < _n);
        scc.add_edge(2 * i + (f ? 0 : 1), 2 * j + (g ? 1 : 0));
        scc.add_edge(2 * j + (g ? 0 : 1), 2 * i + (f ? 1 : 0));
    }
    bool satisfiable() {
        auto id = scc.scc_ids().second;
        for (int i = 0; i < _n; i++) {
            if (id[2 * i] == id[2 * i + 1]) return false;
            _answer[i] = id[2 * i] < id[2 * i + 1];
        }
        return true;
    }
    std::vector<bool> answer() { return _answer; }
 
private:
    int _n;
    std::vector<bool> _answer;
    scc_graph scc;
};
 
int main(){
    int n, d; cin >> n >> d;
    vector<int> x(n), y(n);
    for (int i = 0; i < n; i++) cin >> x[i] >> y[i];
 
    two_sat data(n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (i == j) continue;
            if (abs(x[i] - x[j]) < d) data.add_clause(i, false, j, false);
            if (abs(x[i] - y[j]) < d) data.add_clause(i, false, j, true);
            if (abs(y[i] - x[j]) < d) data.add_clause(i, true, j, false);
            if (abs(y[i] - y[j]) < d) data.add_clause(i, true, j, true);
        }
    }
 
    if (!data.satisfiable()) {
        cout << "No" << "\n";
        return 0;
    }
    cout << "Yes" << "\n";
    auto ans = data.answer();
    for (int i = 0; i < n; i++) cout << (ans[i] ? x[i] : y[i]) << "\n";
    return 0;
}