import sys
from collections import deque

def main():
    N = int(sys.stdin.readline())
    P = list(map(int, sys.stdin.readline().split()))
    
    i_list = list(range(1, N+1))[::-1]  # 轮次按从大到小排序
    Q = deque(range(1, N+1))
    
    total = 0
    
    for i in i_list:
        p = P[i-1]
        if Q[-1] > p:
            total += i
            Q.pop()
        elif Q[0] < p:
            total -= i
            Q.popleft()
        else:
            Q.popleft()
    
    print(total)

if __name__ == "__main__":
    main()