#include<bits/stdc++.h>
using namespace std;
class point{
public:
int x, y;
point(int x__, int y__){
x = x__;
y = y__;
}
int gex(){
return x;
}
int gey(){
return y;
}
};
class cmp{
public:
bool operator()(point a, point b){
return a.x < b.x;
}
};
int main() {
int n, k;
cin >> k >> n;
int a[k][n];
for(int i = 0; i < k; i++){
for(int j = 0; j < n; j++){
cin >> a[i][k];
}
}
int arr[k * n];
priority_queue< point, vector<point>, cmp > pq;
vector<int> v(k, 1);
for(int i = 0; i < k; i++){
pq.push(point(a[i][0], i));
}
int i = 0;
while(!pq.empty()){
point p = pq.top();
pq.pop();
int x = p.x;
int j = p.y;
j;
arr[i] = x;
i++;
if(v[j] < n){
pq.push(point(a[j][v[j]], j));
v[j]++;
}
}
for(i = 0; i < k * n; i++){
cout << arr[i] << " ";
}
cout << "\n";
return 0;
}
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