public class NumberToWords {
private static final String[] BELOW_TWENTY = {"", "one", "two", "three",
"four", "five", "six", "seven", "eight", "nine",
"ten", "eleven", "twelve",
"thirteen", "fourteen", "fifteen", "sixteen",
"seventeen", "eighteen",
"nineteen"};
private static final String[] TENS = {"", "", "twenty", "thirty", "forty",
"fifty", "sixty", "seventy", "eighty", "ninety"};
public static void main(String[] args) {
// Manually handling input without using imports
System.out.println("Enter an integer between -999,999,999 and
999,999,999:");
int number = readInput();
// Convert the number to words and print it
System.out.println("In words: " + numberToWords(number));
}
// Method to read integer input without using Scanner or imports
public static int readInput() {
StringBuilder input = new StringBuilder();
char c;
boolean isNegative = false;
try {
while ((c = (char) System.in.read()) != '\n') {
if (c == '-') {
isNegative = true;
} else if (Character.isDigit(c)) {
input.append(c);
}
}
} catch (Exception e) {
System.out.println("Error reading input.");
}
// Convert input to integer
int number = Integer.parseInt(input.toString());
return isNegative ? -number : number;
}
public static String numberToWords(int num) {
if (num == 0) {
return "zero";
}
if (num < 0) {
return "negative " + numberToWords(-num);
}
return convert(num);
}
private static String convert(int num) {
if (num < 20) {
return BELOW_TWENTY[num];
} else if (num < 100) {
return TENS[num / 10] + ((num % 10 != 0) ? " " + BELOW_TWENTY[num % 10]
: "");
} else if (num < 1000) {
return BELOW_TWENTY[num / 100] + " hundred" + ((num % 100 != 0) ? " " +
convert(num % 100) : "");
} else if (num < 1000000) {
return convert(num / 1000) + " thousand" + ((num % 1000 != 0) ? " " +
convert(num % 1000) : "");
} else {
return convert(num / 1000000) + " million" + ((num % 1000000 != 0) ? "
" + convert(num % 1000000) : "");
}
}
}
