import java.io.IOException;
import java.io.InputStream;
import java.util.*;
import java.math.BigInteger;
 
public class Main implements Runnable {
	
	static int mod = 1000000007;

    public static void main(String[] args) {
    	new Thread(null, new Main(), "", 16 * 1024 * 1024).start();
    }
    
    public void run() {
        FastScanner sc = new FastScanner();

        int n = sc.nextInt();
        int[] a = sc.nextIntArray(n);
        
		int max = Integer.MIN_VALUE;
		int maxid = -1;
		
		for(int i=0;i<n;i++){
			if(a[i]>max){
				max = a[i];
				maxid = i;
			}
		}
        
		int min = Integer.MAX_VALUE;
		int minid = -1;
		for(int i=0;i<n;i++){
			if(a[i]<=min){
				min = a[i];
				minid = i;
			}
		}
        
		int nowmax = max;
		int nowmin = min;
		for(int i=0;i<n;i++){
			if(i==maxid || i==minid){
				continue;
			}
			if(a[i]>0){
				nowmin -= a[i];
			}
			else{
				nowmax -= a[i];
			}
		}
		System.out.println(nowmax - nowmin);
		
		nowmax = max;
		nowmin = min;
		
		for(int i=0;i<n;i++){
			if(i==maxid || i==minid){
				continue;
			}
			if(a[i]>0){
				System.out.println(nowmin + " " + a[i]);
				nowmin -= a[i];
			}
			else{
				System.out.println(nowmax + " " + a[i]);
				nowmax -= a[i];
			}
		}
		System.out.println(nowmax + " " + nowmin);
		
    }
    
	//配列の最大値
	static int max(int[] a){
		int max = Integer.MIN_VALUE;
		for(int i:a){
			if(i>max){
				max = i;
			}
		}
		return max;
	}
	//配列の最小値
	static int min(int[] a){
		int min = Integer.MAX_VALUE;
		for(int i:a){
			if(i<min){
				min = i;
			}
		}
		return min;
	}
	

}

class FastScanner {
	private final InputStream in = System.in;
	private final byte[] buffer = new byte[1024];
	private int ptr = 0;
	private int buflen = 0;
	private boolean hasNextByte() {
		if (ptr < buflen) {
			return true;
		} else {
			ptr = 0;
			try {
				buflen = in.read(buffer);
			} catch (IOException e) {
				e.printStackTrace();
			}
			if (buflen <= 0) {
				return false;
			}
		}
		return true;
	}
	private int readByte() {
		if (hasNextByte())
			return buffer[ptr++];
		else
			return -1;
	}
	private static boolean isPrintableChar(int c) {
		return 33 <= c && c <= 126;
	}
	public boolean hasNext() {
		while (hasNextByte() && !isPrintableChar(buffer[ptr]))
			ptr++;
		return hasNextByte();
	}
	public String next() {
		if (!hasNext())
			throw new NoSuchElementException();
		StringBuilder sb = new StringBuilder();
		int b = readByte();
		while (isPrintableChar(b)) {
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	public long nextLong() {
		if (!hasNext())
			throw new NoSuchElementException();
		long n = 0;
		boolean minus = false;
		int b = readByte();
		if (b == '-') {
			minus = true;
			b = readByte();
		}
		if (b < '0' || '9' < b) {
			throw new NumberFormatException();
		}
		while (true) {
			if ('0' <= b && b <= '9') {
				n *= 10;
				n += b - '0';
			} else if (b == -1 || !isPrintableChar(b)) {
				return minus ? -n : n;
			} else {
				throw new NumberFormatException();
			}
			b = readByte();
		}
	}
	public int nextInt() {
		long nl = nextLong();
		if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)
			throw new NumberFormatException();
		return (int) nl;
	}
	public int[] nextIntArray(int n){
		int[] a = new int[n];
		for(int i=0;i<n;i++){
			a[i] = nextInt();
		}
		return a;
	}
	public Integer[] nextIntegerArray(int n){
		Integer[] a = new Integer[n];
		for(int i=0;i<n;i++){
			a[i] = nextInt();
		}
		return a;
	}
	public double nextDouble() {
		return Double.parseDouble(next());
	}
}

Measured memory_bytes: 73692