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c_cpp
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#include "bits/stdc++.h"
using namespace std;
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x...)
#endif
using ll = long long;
#ifndef LOCAL
constexpr int N = 2e5;
#else
constexpr int N = 100;
#endif
constexpr int K = 7;
constexpr int M = 2187;
int n, k;
int a[K][N];
int cnt[M];
vector<int> ids[M];
bool match(int am, int bm) {
for (int i = 0; i < k; i++) {
if (am % 3 == bm % 3 && am % 3 != 2) return false;
am /= 3;
bm /= 3;
}
return true;
}
struct edge {
int v, c, f;
edge* rev;
};
vector<edge> g[M + 2];
void addEdge(int u, int v, int st) {
g[u].emplace_back(v, st, 0, nullptr);
g[v].emplace_back(u, 0, 0, &g[u].back());
g[u].back().rev = &g[v].back();
}
int d[M + 2];
bool bfs() {
fill(d, d + M + 2, -1);
queue<int> q;
q.push(M);
d[M] = 0;
while (!q.empty()) {
int t = q.front();
q.pop();
if (t == M + 1) return true;
for (auto &[v, c, f, rev] : g[t]) {
if (c - f > 0 && d[v] == -1) {
d[v] = d[t] + 1;
q.push(v);
}
}
}
return false;
}
int ptr[M + 2];
int dfs(int u, int flow) {
if (!flow) return 0;
if (u == M + 1) return flow;
for (int &to = ptr[u]; to < (int)g[u].size(); to++) {
if (d[g[u][to].v] != d[u] + 1) continue;
int pushed = dfs(g[u][to].v, min(flow, g[u][to].c - g[u][to].f));
if (pushed) {
g[u][to].f += pushed;
g[u][to].rev->f -= pushed;
return pushed;
}
}
return 0;
}
int dinic() {
int flow = 0;
while (bfs()) {
fill(ptr, ptr + M + 2, 0);
while (int pushed = dfs(M, INT_MAX)) {
flow += pushed;
}
}
return flow;
}
void test_case() {
cin >> n >> k;
for (int j = 0; j < n; j++) {
for (int i = 0; i < k; i++) {
cin >> a[i][j];
}
}
for (int i = 0; i < k; i++) {
int tmp[n];
copy(a[i], a[i] + n, tmp);
sort(tmp, tmp + n);
double median = (tmp[n / 2 - 1] + tmp[n / 2]) / 2.0;
for (int j = 0; j < n; j++) {
if (a[i][j] > median) {
a[i][j] = 1;
} else if (a[i][j] < median) {
a[i][j] = 0;
} else {
a[i][j] = 2;
}
}
}
for (int i = 0; i < n; i++) {
int val = 0, mult = 1;
for (int j = k - 1; j >= 0; j--) {
val += a[j][i] * mult;
mult *= 3;
}
ids[val].push_back(i);
}
int MX = 1;
for (int i = 0; i < k; i++) {
MX *= 3;
}
for (int am = 0; am < MX / 3; am++) {
addEdge(M, am, ids[am].size());
}
for (int bm = MX / 3; bm < MX; bm++) {
addEdge(bm, M + 1, ids[bm].size());
}
for (int am = 0; am < MX / 3; am++) {
for (int bm = MX / 3; bm < MX; bm++) {
if (match(am, bm)) {
addEdge(am, bm, min(ids[am].size(), ids[bm].size()));
}
}
}
if (dinic() == n / 2) {
cout << "YES\n";
for (int u = 0; u < MX / 3; u++) {
for (auto &[v, c, f, rev] : g[u]) {
while (f--) {
cout << ids[u].back() + 1 << ' ' << ids[v].back() + 1 << '\n';
ids[u].pop_back();
ids[v].pop_back();
}
}
}
} else {
cout << "NO\n";
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
int tests = 1;
// cin >> tests;
while (tests--) {
test_case();
}
return 0;
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