contest.py

n = int(input())
a = [int (i) for i in input().split()]
mx=max(a)
maxm=0
k=a.index(mx)
for i in range(k+1,n-1):
    if a[i] % 10 == 5 and a[i]>a[i+1] and maxm<a[i]:
        maxm=a[i]
a.sort(reverse = True)
num = 1
if maxm == 0:
    print("0")
else:
    my=a.index(maxm)
    print(my+1)