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#include <cstdio>
#include <vector>
using namespace std;

int main() {
	int k; scanf("%d", &k);
	vector<int> v;
	while (k > 1) {
		v.push_back(k % 2);
		k >>= 1;
	}

	int n = v.size() * 2 + 2;
	printf("%d\n", n);
	for (int i=0; i<v.size(); ++i) {
		printf("%d %d\n", 2 * i + 2, 2 * i + 3);
		int extra = v[i] * (n + 1) - 1;
		printf("%d %d\n", 2 * i + 3, extra);
	}
	printf("%d -1\n", n);
	printf("-1 -1\n");

	return 0;
}