Round-Robin Printer

Difficulty: 1400 3000 ms 128 MB

math implementation

N print jobs (page counts given) share a printer that cycles through jobs in order, printing ONE page of each unfinished job per pass, starting from job 1. When does job K print its final page? (Total pages printed up to and including that moment.)

Input: the first line has N and K; the second line has the N page counts.

Output: the number of pages printed when job K finishes.

Constraints:

• 1 ≤ K ≤ N ≤ 10⁵
• 1 ≤ p_i ≤ 10⁴

Sample Tests

3 2
1 5 3

9

1 1
7

7

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