#include <iostream>
#include <algorithm>
#include <vector>
int main() {
int n,m;
std::cin >> n >> m;
std::vector<int> v;
for (int i = 0; i != n * m; i++) {
int x;
std::cin >> x;
v.push_back(x);
}
std::sort(v.begin(), v.end());
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
std::cout << v[j * n + i] << " ";
std::cout << '\n';
}
}
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