So apperently i'm reading a document written in Chinese about recusion for learning purpose. In that document there is a problem that seems to relate to IOI but i cannot understand what it's saying even after i have it translated to Vietnamese(This used to be "English", typo) with Google translator. I've done a bit of googling about IOI 99 but non of the problems i encountered seems to be what i'm looking for. Could the Chinese community on Codeforces please provide me with a proper translation of the problem ?

Here's the original text: 01序列：近来IOI的专家们在进行一项有关二进制数的研究，研究设计的一个统计问题令他们大伤脑筋。问题是这样的：对于一个自然数n，可以把他转换成对应的二进制数 ，其中：n = a_k*2^k + a_(k-1)*2^(k-1) + ... + a_1*2^1+a_0；而且a_i=0或1(0<=i<k)，a_k=1。如：10=1010；5=101。我们统计一下a_0~a_k，这k+1个数中0的个数和1的个数。如果在这k+1个数中，0的个数比1的个数多，就称为A类数。现在的任务是，对于一个给定的m，求1~m中a类数的个数。

Why didn't you just try google translate? The translation won't be a hundred percent accurate but it would surely be understandable, considering you have a proper sense of the English language.

Anyway, I pasted it to GTranslate and fixed some major errors for you. Hope it helps :)

01 Sequence: Recently, IOI experts are conducting a study on binary numbers, and a statistical problem in the design has given them a big headache. The problem is this: for a natural number n, you can convert it to the corresponding binary number, where: n = a_k*2^k + a_(k-1)*2^(k-1) + ... + a_1 *2^1+a_0; and a_i=0 or 1 (0<=i<k), a_k=1. Such as: 10 = 1010; 5 = 101. Let's count a_0~a_k, the number of 0s and the number of 1s in this k+1 number. If the number of 0s is larger than the number of 1 among the k+1 numbers, it is called the class A number. The task now is to find the number of class A numbers in 1~m for a given m.

(Hope I made the Chinese community proud)

Why didn't you just try google translateThat's because people like him love to get spoonfed.

C'mon man don't be rude

Thanks a lot shaf_wa_nur ! I did use GTranslate but my destination language is set as Vietnamese (my mother tongue) and the translation is really confusing, that's why i decided to go to Codeforces to ask :) Should have set the destination to english though, my bad.