Độ khó: Dễ (1/4 điểm)

Sample Input

4 3 2

Sample Output

12

Độ khó: Trung bình (2/4 điểm)

Sample Input

20

Sample Output

6

Độ khó: Trung bình (2/4 điểm)

Sample Input 1

2
-1 2

Sample Output 1

0

Sample Input 2

4
2 5 -4 -7

Sample Output 2

12

Độ khó: Khá (3/4 điểm)

Sample Input 1

4 1 1000 9999

Sample Output 1

9999

Sample Input 2

4 3 8 29

Sample Output 2

9829

Sample Input 3

12 3 5000 9999

Sample Output 3

999999989997

Sample Input 4

11 4 4 2397

Sample Output 4

99999998997