#include <fstream>

using std::ifstream;
using std::ofstream;

const int MAX_N = 1000100;
const int MAX_NODE = 2000100;

ifstream f("huffman.in");
ofstream g("huffman.out");

int k, n, i, lim, p1, p2, u1, u2, c[MAX_N], j;
long long niv[MAX_NODE], wb[MAX_NODE][2], w[MAX_NODE], b[MAX_NODE], lg, a[MAX_N];

void dfs(int nod, int nivel, long long bb) {
niv[nod] = nivel;
b[nod] = bb;
if (wb[nod][1]) {
dfs(wb[nod][1], nivel + 1, bb << 1);
dfs(wb[nod][0], nivel + 1, (bb << 1) + 1);
}
}

int main() {
f >> n;
for (i = 1; i <= n; ++i)
f >> a[i];
k = 0;
lim = 2 * n - 1;
p1 = 1;
u1 = n;
p2 = 1;
u2 = 0;
while (k < lim) {
if (a[p1 + 1] && (a[p1 + 1] <= w[c[p2]] || p2 > u2)) {
w[++k] = a[p1];
lg += w[k];
w[++k] = a[++p1];
lg += w[k];
w[++k] = w[k - 2] + w[k - 1];
lg += w[k];
c[++u2] = k;
a[p1] = wb[k][1] = k - 2;
a[p1 - 1] = wb[k][0] = k - 1;
++p1;
} else if (w[c[p2 + 1]] && (w[c[p2 + 1]] <= a[p1] || p1 > u1)) {
w[++k] = w[c[p2]] + w[c[p2 + 1]];
lg += w[k];
c[++u2] = k;
  wb[k][0] = c[p2 + 1];
  wb[k][1] = c[p2];
  p2 += 2;
} else if (p1 <= u1 && p2 <= u2 && w[c[p2]] <= a[p1] &&
           (a[p1] <= w[c[p2 + 1]] || p2 == u2)) {
  w[++k] = a[p1];
  lg += w[k];
  w[++k] = w[c[p2]] + w[k - 1];
  lg += w[k];
  c[++u2] = k;
  a[p1] = wb[k][0] = k - 1;
  wb[k][1] = c[p2];
  ++p1;
  ++p2;
} else {
  w[++k] = a[p1];
  lg += w[k];
  w[++k] = w[c[p2]] + w[k - 1];
  lg += w[k];
  c[++u2] = k;
  wb[k][0] = c[p2];
  a[p1] = wb[k][1] = k - 1;
  ++p1;
  ++p2;
}

}
dfs(lim, 0, 0);
lg -= w[lim];
g << lg << '\n';
for (i = 1; i <= n; ++i)
g << niv[a[i]] << ' ' << b[a[i]] << '\n';
return 0;
}