def get_wood_amount(trees, cut_height):
    # 计算砍下的木材总长度
    wood = sum(tree - cut_height for tree in trees if tree > cut_height)
    return wood

def find_max_height(trees, m):
    low, high = 0, max(trees)
    result = 0

    while low <= high:
        mid = (low + high) // 2
        wood = get_wood_amount(trees, mid)

        if wood >= m:
            result = mid
            low = mid + 1
        else:
            high = mid - 1

    return result

# 读取输入
n, m = map(int, input().split())
trees = list(map(int, input().split()))

# 计算结果
max_cut_height = find_max_height(trees, m)

# 输出结果
print(max_cut_height)