任意进制数的转换。

设计思路：求n整除d的余数，就能得到n的d进制数的最低位数字，重复上述步骤，直至n为0，一次得到n的d进制数表示的最低位至最高为数字。由各位数字取出相应的字符，就能得到n的d进制的字符。

主函数是用于测试trans函数，要求输入一个待转换的正整数，接着调用trans函数进行转换，并输出改正知识的2-16进制数转换结果。-Arbitrary hexadecimal number conversion. Design: n divisible by d for the remainder, we can get n the d-band minimum-digit number, repeat the above steps until n is 0, the first to be n the d-band minimum number of spaces to express the highest figure. You figure out from the corresponding characters, can be n the d-band characters. Main function is for testing trans function, asked to enter a positive integer to be converted, and then call the function trans conversion, and output to correct knowledge-band digital conversion results 2-16.