No Thanks!

No Thanks! is a board game played with number cards from $3$ to $35$. Players win number cards in auctions. At the end, each player scores the cards they hold as follows.

1. Sort the integers in ascending order, then split them into groups of consecutive runs where each neighboring pair differs by $1$.
2. For each group, take its smallest number. The score is the sum of these smallest numbers.

For example, if the cards are $6$, $7$, $10$, $12$, $13$, $14$, $15$, $20$, $21$, $22$, they form the $4$ groups $\[6, 7]$, $\[10]$, $\[12, 13, 14, 15]$, and $\[20, 21, 22]$. The score is $6 + 10 + 12 + 20 = 48$.

Write a program that computes the score from the cards a player holds.

The first line contains $N$, the number of cards.

The second line contains the $N$ integers $x_i$ written on the cards, separated by spaces, in ascending order.

Print the score computed by the rules above on the first line.

• $1 \le N \le 33$
• For all $1 \le i \le N$, $3 \le x_i \le 35$
• For all $1 \le i \le N-1$, $x_i < x_{i+1}$