Arrange the natural numbers from small to large without intervals to get a series of numbers: 123456789101112131415..., what is the 1000th number from left to right in this series of numbers.
将自然数从小到大无间隔的排列起来，得到一串数码：123456789101112131415…，这串数中从左到右数第1000个数码是多少．
<result>3</result>