base-conversion

How can I convert a number contained in a string from any base to any other base? Bases can be anything i.e.: 2, 16, 10, 4, 8, 9. I'm expecting the user to enter the base number. The user will enter the output base (the base to be converted to). The user will enter the number he wants to convert. Pre thoughts: I will save the input base and the output base in variables. Then I'll save the number he enters in a string (because he could enter any kind of number (hex, binary, base-5..). I'm just trying to figure out how to convert that string to a number so i can convert it to the output base.

Is there a c++ structure or template (in any library) that allows me to do conversion between decimal and any other base (much like what bitset can do) ? Yes, you can use unsigned int : unsigned int n = 16; // decimal input unsigned int m = 0xFF; // hexadecimal input std::cout << std::dec << "Decimal: " << n << ", " << m << std::endl; std::cout << std::hex << "Hexadecimal: 0x" << n << ", 0x" << m << std::endl; Octal is also supported, though for other bases you had best write your own algorithm - it's essentially a three-liner in C++: std::string to_base(unsigned int n, unsigned int base) {

I need to print some data (a little bit strange formatted). I was writing it in PHP with if ($num%10==9) but it was impossible for me to get correct output. So take a look at this for example. We have x of files in folder. For this example x=36. X is always known. Output should look like this: 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10 11 ... 19 1a ... 1f 20 ... 24 Sorry for the such a long "list" but I believe that you know what I need now. So, after each number which ends with 9 we have num(a,b,c,d,e,f) and then number which follows previous number with 9 on the end. (Ex. 3a...3f,40..49

I've recently learnt about CNS and FNS , and since they look so elegant to me, I decided to try and implement methods to generate combinations and permutations using those techniques. I finished my method to convert from n choose k combinations to a CSN rank and vice-versa but I'm banging my head against the wall trying to do the same with n choose k (unique) permutations. Thanks to @Joshua I got the unranking (FNS to permutation) method working: function Pr_Unrank($n, $k, $rank) { // rank starts at 1 if ($n >= $k) { if (($rank > 0) && ($rank <= Pr($n, $k))) { $rank--; $result = array();

Could you provide a convincing explanation, or a mathematical proof, to why the following function calculates the negabinary representation of a given number? function quickNegabinary(number) { var mask = 0xAAAAAAAA; return ((number + mask) ^ mask).toString(2); } Negabinary notation Negabinary notation uses a radix of -2. This means that, as in every number system with a negative base, every other bit has a negative value: position: ... 7 6 5 4 3 2 1 0 binary: ... 128 64 32 16 8 4 2 1 negabinary: ... -128 +64 -32 +16 -8 +4 -2 +1 Quick conversion method The quick binary→negabinary conversion

Is there a way to take any number, from say, 1 to 40000 and generate an 8 character hash? I was thinking of using base_convert but couldn't figure out a way to force it to be an 8 character hash. Any help would be appreciated! Nathan Osman Why don't you just run md5 and take the first 8 characters? Because you are wanting a hash, it doesn't matter whether portions are discarded, but rather that the same input will produce the same hash. $hash = substr(md5($num), 0, 8); >>> math.exp(math.log(40000)/8) 3.7606030930863934 Therefore you need 4 digit-symbols to produce a 8-character hash from 40000

This question already has an answer here: In Java how do you convert a decimal number to base 36? 10 answers I'm in this Object Oriented class, but I just don't know how to do this. I know basic fundamentals but nothing like this. I am asked to create a program that converts #'s base 10 to base 2, base 8,and base 16. Then, after we are asked to convert it back from 2,8,16 to base 10. I have gathered some information from other websites and I actually ended up editing a bit of it. Please help! I would prefer it if you guys actually helped and edited yourselves and sent it to me, but if that is