Problem7166--ABC251 —— E - Takahashi and Animals

7166: ABC251 —— E - Takahashi and Animals

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

Takahashi is with $N$ animals. The $N$ animals are called Animal $1$, Animal $2, \ldots$, Animal $N$.
Takahashi will perform the following $N$ kinds of action. Each action can be performed any number of (possibly zero) times.
  • Pay $A_1$ yen (the currency in Japan) to feed Animals 1 and 2.
  • Pay $A_2$ yen to feed Animals 2 and 3.
  • Pay $A_3$ yen to feed Animals 3 and 4.
  • $\cdots$
  • Pay $A_i$ yen to feed Animals i and (i+1).
  • $\cdots$
  • Pay $A_{N-2}$ yen to feed Animals (N-2) and (N-1).
  • Pay $A_{N-1}$ yen to feed Animals (N-1) and N.
  • Pay $A_N$ yen to feed Animals N and 1.
Note that the N-th action above feeds "Animals N and 1."
Print the minimum possible total cost to feed every animal at least once.

Input

Input is given from Standard Input in the following format:
$N$
$A_1\ A_2\ \ldots\ A_N$

Output

Print the minimum possible total cost to feed every animal at least once.

Constraints

$2≤N≤3×10^5$
$1 \leq A_i \leq 10^9$
All values in input are integers.

Sample 1 Input

5
2 5 3 2 5

Sample 1 Output

7
If Takahashi performs the 1-st, 3-rd, and 4-th actions once each, Animals 1, 2, 3, 4, and 5 are fed once, once, once, twice, once, respectively, so every animal is fed at least once. The total cost to do so is $A_1 + A_3 + A_4 = 2 + 3 + 2 = 7$ yen, which is the minimum possible.

Sample 2 Input

20
29 27 79 27 30 4 93 89 44 88 70 75 96 3 78 39 97 12 53 62

Sample 2 Output

426

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