def log_base_10(n):
    if n == 0:
        return float('-inf')  # Logarithm of 0 is undefined
    count = 0
    while n >= 1:
        n /= 10
        count += 1
    return count


if __name__ == '__main__':
    n = 102
    out = 0
    for i in range(1, n + 1):
        power = (i // 10 + 1)

        # print(i, i / 10, log_base_10(i), pow(10, log_base_10(i) - 1), pow(10, power))
        out = out * pow(10, log_base_10(i)) + i

    print(out)