Base Conversion

base_conversion.clj

(ns cs101-clojureworkspace.base-conversion
  (:require [clojure.string :as str]
            [sc.api :as scc]))


(def charset "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")

(defn convertToBase10 [^String number base]
  (reduce + (map *
                 (map (partial str/last-index-of charset) (-> number (str/upper-case) (reverse)))
                 (iterate (partial * base) 1))))

(defn convertFromBase10 [number base]
  (let [place-values (reverse (take-while
                                (partial >= number)
                                (iterate (partial * base) 1)))]
    (->> place-values
         (reduce (fn [[out remainder] place-value]
                   [(cons (get charset (quot remainder place-value)) out)
                    (rem remainder place-value)])
                 [() number])
         (first)
         (reverse)
         (apply str))))

BaseConversion.java

package edu.memphis.cs101.jarrettatkinson;

import java.util.Scanner;

public class BaseConversion {
    private static String characterSet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    
    
    public static void main(String[] args) throws InterruptedException {
        Scanner input = new Scanner(System.in);
        
        System.out.print("\nPlease type your number: ");
        String number = input.nextLine();
        System.out.print("\nPlease enter your base: ");
        int base = input.nextInt();
        
        System.out.print("\nPlease enter your base you want to convert to: ");
        int baseTo = input.nextInt();

        int base10ans = readToBase10(number,base);
        String out = convertNumberToBase(base10ans, baseTo);
        
        System.out.println("\nYour answer: " + out);
        
            
    }
    
    private static int readToBase10(String number, int base) {
        number = number.toUpperCase();
        int sum = 0;
        for (int i = 0; i < number.length(); i++) {
            int charValue = characterSet.indexOf(number.charAt((number.length() - 1) - i));
            sum += charValue * Math.pow(base, i);
        }
        
        return sum;
    }
    
    private static String convertNumberToBase(int number, int base) {
        int digitCount = 0;
        while (number >= Math.pow(base, digitCount)) digitCount++;
        
        StringBuilder result = new StringBuilder();
        int remainingNumber = number;
        for (int i = digitCount; i >= 0 && remainingNumber != 0; i--) {
            int placeValue = (int)Math.pow(base, i);
            int digitValue = remainingNumber / placeValue;
            remainingNumber = remainingNumber % placeValue;
            result.append(characterSet.charAt(digitValue));
        }
        
        return result.toString();
    }
}