def main():
    n = int(input())
    c_n = list(map(int, input().split()))

    ans = []
    for idx, c_i in enumerate(c_n):
        for _ in range(c_i):
            ans.append(idx + 1)

    ans.reverse()
    print("".join(map(str, ans))[:n])


if __name__ == "__main__":
    main()