#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

int main() {
	int n;
	cin >> n;
	vector<pair<int, int>> v(n);
	for(int i = 0; i < n; ++i) {
		v[i].first = i + 1;
		cin >> v[i].second;
	}
	int k = 0;
	while(k * k < n) ++k;
	auto key = [&](auto x) {
		auto first  = x.first / k;
		auto second = (first % 2 == 0) ? x.second : -x.second;
		return std::pair{first, second};
	};
	sort(begin(v), end(v), [&](auto x, auto y) { return key(x) < key(y); });
	for(auto x : v) cout << x.first << " " << x.second << endl;
}