from sys import exit
from sys import stdin

n = int(stdin.readline())
numbers = map(int, stdin.readline().split())
reminders = {}

sum = 0

for it in xrange(n):
    sum += numbers[it]
    reminder = sum % n

    if reminder == 0:
        print it + 1
        print " ".join(map(str, range(1, it + 2)))
        exit(0)
    elif reminders.get(reminder) != None:
        print it + 1 - reminders[reminder]
        print " ".join(map(str, range(reminders[reminder] + 1, it + 2)))
        exit(0)
    reminders[reminder] = it + 1