====== 합의 최소 ======

===== 풀이 =====
  * 풀이는 [[https://github.com/ssu-sccc/2025scon/blob/main/editorial-slide.pdf|에디토리얼]] 참고
  * 시간복잡도는 O(1)

===== 코드 =====
<dkpr py>
"""Solution code for "BOJ 33910. 합의 최소".

- Problem link: https://www.acmicpc.net/problem/33910
- Solution link: http://www.teferi.net/ps/problems/boj/33910

Tags: [ad hoc]
"""

INF = float('inf')


def main():
    N = int(input())  # pylint: disable=unused-variable
    A = [int(x) for x in input().split()]

    answer, min_val = 0, INF
    for a_i in reversed(A):
        if a_i < min_val:
            min_val = a_i
        answer += min_val
    print(answer)


if __name__ == '__main__':
    main()
</dkpr>

{{tag>BOJ ps:problems:boj:실버_5}}