【问题描述】编写函数itob(n,s,b),用于把整数n转换成以b为基的字符串并存储到s中. 编写程序,使用函数itob(n,s,b)将输入的整数n,转换成字符串s,将s输出.转换后的字符串从最高的非零位开始输出。如果n为负数，则输出的字符串的第一个字符为’-’。b为大于1小于37的任意自然数值。当b=2时，输出字符只可能是’0’和’1’；当b=16时，输出字符串中可能含有字符为’0’-’9’，’a’-’f’(字母以小写输出)。b还可以是其它数值。比如输入n=33,b=17，则输出33的17进制值为"1g"。

【输入形式】控制台输入整数n和b，其中n可以为负数。n和b以空格分隔.

【输出形式】控制台输出转化后的字符串s.

【样例输入】5 2

【样例输出】101

【样例说明】5的二进制就是101

【评分标准】结果完全正确得20分，每个测试点4分。提交程序名为：itob.c-[Problem Descr iption] Write a function itob (n, s, b), is used to convert the integer n base b string and stored in s. Written procedures, use the function itob (n, s, b) the input integer n, converted to a string s, the s output. strings converted from the highest non-zero bit to start output. If n is negative, the first character of the output is　- . b is greater than a value of less than 37 of any nature. When b = 2, the output character can only be　0　and　1　 When b = 16, the output string may contain characters　0　-　9 ,　a -　f　(letter in lower output). b may also be other values​ ​ . For example, enter n = 33, b = 17, the output 17 hex value "1g" 33 s.

[Form] input console input integer n and b, where n can be negative. n and b separated by a space.

[Output format] console output after conversion string s.

Sample input [52]

Sample output] 101

[Descr iption] binary sample 5 is 101

[Standard] results entirely correct score 20 points, 4 points for each test poin