#include <bits/stdc++.h>
using namespace std;
struct Edge {
int u, v, w;
Edge(int _u = 0, int _v = 0, int _w = 0): u(_u), v(_v), w(_w) {}
};
struct DSU {
vector<int> par, rank;
DSU(int n): par(n), rank(n) {
iota(par.begin(), par.end(), 0);
}
int find(int u) {
return par[u] == u ? u : par[u] = find(par[u]);
}
bool unite(int u, int v) {
u = find(u); v = find(v);
if (u == v) return false;
if (rank[u] < rank[v]) swap(u, v);
par[v] = u;
if (rank[u] == rank[v]) rank[u]++;
return true;
}
};
const int MAX_A = 1e7 + 1;
int nxt[MAX_A], freq[MAX_A];
vector<int> p;
int main() {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n, x, maxval = 0;
cin >> n;
for (int i = 0; i < n; ++i) {
cin >> x;
if (!freq[x]) p.push_back(x);
freq[x] = 1;
maxval = max(maxval, x);
}
sort(p.begin(), p.end()); // p is already unique
n = p.size();
for (int i = 0; i < n - 1; ++i) {
nxt[p[i]] = i;
for (int j = p[i] + 1; j < p[i + 1]; ++j)
nxt[j] = i + 1;
}
nxt[p[n - 1]] = n - 1;
int mx = p[n - 1];
vector<Edge> edges;
int maxWeight = 0;
for (int i = 0; i < n; ++i) {
int pi = p[i];
if (pi + 1 <= mx) {
int v = nxt[pi + 1];
int w = p[v] % pi;
edges.emplace_back(i, v, w);
maxWeight = max(maxWeight, w);
}
for (int j = pi; j <= mx;) {
int v = nxt[j];
int w = p[v] % pi;
edges.emplace_back(i, v, w);
maxWeight = max(maxWeight, w);
if (p[v] / pi == 0) break;
j = (p[v] / pi) * pi + pi;
}
}
// Count-based bucket sort with limited memory
vector<vector<Edge>> bucket(maxWeight + 1);
for (const Edge &e : edges)
bucket[e.w].push_back(e);
vector<Edge> sorted;
for (int w = 0; w <= maxWeight; ++w)
for (const Edge &e : bucket[w])
sorted.push_back(e);
DSU dsu(n);
long long total = 0;
int used = 0;
for (const auto &[u, v, w] : sorted) {
if (dsu.unite(u, v)) {
total += w;
if (++used == n - 1) break;
}
}
cout << total << '\n';
}
