#include <iostream>
#include <vector>
#include <cmath>
int main()
{
	int width;//宽度
	while (std::cin >> width && width != 0) {
		std::vector<std::pair<int, int>> image;//图像RLE序数对
		int firstp, secondp;//初始化序数对
		// 记录序数对
		while (std::cin >> firstp && std::cin >> secondp && firstp != 0 && secondp != 0) {
			image.push_back(std::make_pair(firstp, secondp));
		}

		//适度 解压
		std::vector<std::pair<int, int>> edge1;
		for (std::vector<std::pair<int, int>>::const_iterator it = image.begin();it != image.end();it++) {
			if (it->second / width >= 3) {
				edge1.push_back(std::make_pair(it->first, width));
				edge1.push_back(std::make_pair(-1, it->second - width * 2));
				edge1.push_back(std::make_pair(it->first, width));
			}
			else edge1.push_back(std::make_pair(it->first, it->second));
		}

		//完全解压
		std::vector<int> edge2;
		for (std::vector<std::pair<int, int>>::const_iterator it = edge1.begin();it != edge1.end();it++) {
			if (it->first != -1) {
				for (int i = 0;i < it->second;++i)edge2.push_back(it->first);
			}
			else {
				for (int i = 0;i < width;++i)edge2.push_back(-1);
				for (int i = 0;i < (it->second % (2 * width));++i)edge2.push_back(-1);
				//-1的个数：width+pair.second%(2*width)
			}
		}

		//计算
		std::vector<int> result1(static_cast<int>(edge2.size()), 0);
		int height = static_cast<int>(edge2.size()) / width;//长度
		for (int x = 0;x < width;++x) {
			for (int y = 0;y < height;++y) {
				if (edge2[width * y + x] == -1)continue;
				int maxabdiff = 0;
				int currentabdiff = 0;
				for (int dx = -1;dx <= 1;++dx) {
					for (int dy = -1;dy <= 1;++dy) {
						if (dy == 0 && dx == 0)continue;
						if (!(y + dy >= 0 && x + dx >= 0 && y + dy < height && x + dx < width))continue;
						if (edge2[width * (y + dy) + (x + dx)] == -1)continue;
						currentabdiff = std::abs(edge2[width * (y + dy) + (x + dx)] - edge2[width * y + x]);
						maxabdiff = maxabdiff > currentabdiff ? maxabdiff : currentabdiff;
					}
				}
				result1[width * y + x] = maxabdiff;
			}
		}
		result1.push_back(-2);


		//压缩
		std::vector<std::pair<int, int>> result2;
		int nn = 0;
		int lengthedge1 = static_cast<int>(edge1.size());
		for (int i = 0;i < lengthedge1;++i) {
			if (edge1[i].first != -1) {
				int currentlength = 1;
				int currentValue = -1;
				for (int j = 0;j < edge1[i].second;++j) {
					currentValue = result1[nn++];
					if (currentValue == result1[nn])currentlength++;
					else {
						result2.push_back(std::make_pair(currentValue, currentlength));
						currentlength = 1;
						currentValue = -1;
					}
				}
				if (currentValue != -1)result2.push_back(std::make_pair(currentValue, currentlength - 1));
			}
			else {
				result2.push_back(std::make_pair(0, edge1[i].second));
				nn += width + (edge1[i].second % (2 * width));
			}
		}
		result2.push_back(std::make_pair(-2, 1));


		//再压缩
		std::vector<std::pair<int, int>> result3;
		int lengthresult2 = static_cast<int>(result2.size());
		for (int i = 0;i < lengthresult2 - 1;) {
			int sum = result2[i].second;
			while (result2[i].first == result2[i + 1].first) {
				i++;
				sum += result2[i].second;
			}
			result3.push_back(std::make_pair(result2[i].first, sum));
			i++;
		}


		//输出结果
		std::cout << width << std::endl;
		for (std::vector<std::pair<int, int>>::const_iterator it = result3.begin();it != result3.end();it++) {
			std::cout << it->first << " " << it->second << std::endl;
		}
		std::cout << "0 0" << std::endl;
	}
	std::cout << "0";
	return 0;
}