DISPLEJ

문제

The game "display" is gaining popularity in casinos around the world. The game is run on a big screen visible to all players. A single integer is displayed on the screen, which changes every minute. 

The players attempt to determine the sum of K consecutive numbers, starting from the B-th displayed number. More precisely, if X_n is the n-th number displayed (starting with X₁), then players try to determine the sum X_B + X_B+1 + ... + X_B+K−1. 

Mirko is thrilled with this game and often spends five or six hours calculating sums and growing in debt. Recently he realized that the numbers on screen follow a precise pattern; the same sequence of N integers repeats over and over. 

Help Mirko to find the sought sum, given the sequence of number repeating. 

입력

The first line contains three integers N, K and B, 1 ≤ N ≤ 100, 1 ≤ K ≤ 100, 1 ≤ B ≤ 10⁹. 

The second line contains N non-negative integers less than 100, separated by spaces. This is the sequence that keeps repeating on screen. 

출력

Output the sum on a single line. 

힌트

In the first example, the tenth number displayed is 0, followed by 6 and 8. The sum is 14.

6 3 10
29 6 35 0 6 8

14

5 7 154
1 2 3 4 5

24

2 100 100000
1 0

50