Base Converter

Convert int to binary base 2 10 base 2 = 1010, 3 base 2 = 11

If we want to convert a number to a binary base 2, we let the number mod 2, if the mod number is 0, we insert 0 in the first position, if the mod number is 1, we inser 1 in the first position.

public String convertBase2(int number) {
        if (number==0) {
            return "0";
        }

        StringBuilder sb = new StringBuilder();

        while (number!=0) {
            int temp = number % 2;
            if (temp==0) {
                sb.insert(0, 0);
            } else {
                sb.insert(0, 1);
            }
            number = number / 2;
        }
        return sb.toString();
    }

Convert int to binary base (x), where x is a parameter

解法类似，给出一个所有可能的数字组合。

public String convert(int number, int base) {
        if (number==0) {
            return "0";
        }

        String digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        StringBuilder sb = new StringBuilder();

        while (number!=0) {
            int temp = number % base;
            sb.insert(0, digits.charAt(temp));
            number = number / base;
        }

        return sb.toString();
    }