本书的页码从自然数1 开始顺序编码直到自然数n。书的页码按照通常的习惯编排， 每个页码都不含多余的前导数字0。例如，第6 页用数字6 表示，而不是06 或006 等。数 字计数问题要求对给定书的总页码n，计算出书的全部页码中分别用到多少次数字0，1， 2，…，9-Page of this book started from the natural number 1 until the natural number sequence encoding n. Book page layout in accordance with the usual habits, each page number are non-redundant leading figure 0. For example, the first six figure 6 with express, rather than 06 or 006 and so on. Count the number of questions asked of a given book' s total page number n, to calculate the full book page number in the number of times used separately figure 0,1, 2, ..., 9