import sys
from operator import itemgetter
from collections import defaultdict, deque
import heapq
import bisect

stdin=sys.stdin
sys.setrecursionlimit(10 ** 8)

ip=lambda: int(sp())
fp=lambda: float(sp())
lp=lambda:list(map(int,stdin.readline().split()))
sp=lambda:stdin.readline().rstrip()
Yp=lambda:print('Yes')
Np=lambda:print('No')
inf = 1 << 60
eps = 1e-9
sortkey = itemgetter(0)

###############################################################

N = ip()
A = lp()
ans = 0
for i in range(N):
    if A[i] == N:
        ans -= (i + 1)
    else:
        ans += i + 1

print(ans)