#include <cstdio>
#include <queue>
#define NMAX 1000005
using namespace std;
int n;

struct Node
{
    Node* left, *right;
    long long value;
    int idx;
    
    Node(int val, int givenIdx)
    {
        value = val;
        idx = givenIdx;
        left = right = NULL;
    }
    
    Node(Node* x, Node* y)
    {
        value = (x -> value) + (y -> value);
        left = x; right = y;
    }
};

queue <Node*> A, B;
int m, L[NMAX];
long long result = 0, V[NMAX];

void dfs(Node* node, long long val, int len)
{
    if (node -> left == NULL && node -> right == NULL)
    {
        L[node -> idx] = len;
        V[node -> idx] = val;
        return ;
    }
    result += node -> value;
    
    if (node -> left)   dfs(node -> left, val << 1, len + 1);
    if (node -> right)  dfs(node -> right, (val << 1) + 1, len + 1);
}

void getMin(Node *&a)
{
    if (!A.size() || (B.size() && (A.front() -> value) > (B.front() -> value)))
        a = B.front(), B.pop();
    else
        a = A.front(), A.pop();
}

int main()
{
    freopen("huffman.in", "r", stdin);
    freopen("huffman.out", "w", stdout);
    
    scanf("%d", &n);
    int x;
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &x);
        A.push(new Node(x, i));
    }
    
    Node *a, *b;
    while (A.size() || B.size() >= 2)
    {
        getMin(a);
        getMin(b);
        
        B.push(new Node(b, a));
    }
    
    dfs(B.front(), 0, 0);
    
    printf("%lld\n", result);
    for (int i = 1; i <= n; i++)
        printf("%d %lld\n", L[i], V[i]);
    return 0;
}