#include <bits/stdc++.h>
#define int long long
using namespace std;
const int nmax = 1e6;
int a[nmax + 5];
int32_t main() {
int n; cin >> n;
for(int i = 1; i <= n; ++ i) cin >> a[i];
int ans = 0, c = 1e18;
for(int i = 1; i <= n; ++ i) {
c = min(a[i], c);
ans += 3 * c;
}
cout << ans;
}
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