Convert integer to name - Leetcode 273 - 45 minutes

ConvertIntegerToName.cs

9:32 pm
273. Integer to English Words

Convert a non-negative integer to its english words representation. Given input is guaranteed to be less than 2^31 - 1.
2 billion is max  2,000,000,000 = 2^9

For example,
123 -> "One Hundred Twenty Three"
12345 -> "Twelve Thousand Three Hundred Forty Five"
1234567 -> "One Million Two Hundred Thirty Four Thousand Five Hundred Sixty Seven"


// Int to Words
// 12 -> twelve
// 4012 -> four thousand twelve
// 4000012 -> four million twelve

[0,1,2,3]
[billion, million,  hundred, ""]

1000 ^ ( 3 - i)  - 
int -> number on line 19
go over loop line 18 ->
1000,000,000 -> %1000,000,000 

residue will be 0 - 999 
for the number less than 0 - 999, we will map to 
[100,10,1]
for example, 345
[3, 4, 5]
then concatenate to 3 hundred forty five

string mapToMmeaningfulSentence(int number)
{
// 2, 000,000,000 -> 1, 234, 567, 890 -> forward order, deal with leftmost one -> billion, then work on 234 -> two hundred thirty four, then we know it is from digit 7 to 9, add suffix called million, 
// next work on 567 -> five hundred sixty seven, add suffix called thousand
// next work on 890 -|> eight hundred ninty

var  everyThousand = new int[]{0, 1, 2, 3};
var  everyThousandName = new string[]{"billion", "million", "hundred", ""}; 
var  lessThan20BigerThan10 = new string[]{eleven, tweleve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, ninteen};
var  with0 = new string[]{ten, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninty}; 
var  lessThan10 = new string[]{zero, one, two,three, four, five, six, seven, eight, nine};

// base case 100 -|> one hundred -> 
// 1, 234, 567, 890
//112

int residue = 0; 
int leftover = nummber; /// 112 

var name = ""; 

foreach(int index in everythousand ){   index = 0
  int thousands = 1000^(3 - index);  // 1, 1,000,000, 1000, 1
  residue = number % thousands; // 0, 0, 0, 112
  leftover = number - residum * thousands; // 112, 112, 112, 0
  
  if(residue =  0) // true, treu
  continue;  
  
  // residumme is less than 1000
  // check right most digit
     // 
  var hundredDigit = residum%100; 
  var hudnredName =  lessThan10[hundredDigt]
  name += hundredDigt == 0? "" : hundredName + " hundred";
  
  // check second right most digit
  var twoDigit|Number = residum - hundredDigit * 100;
  var tenthDigit = twoDigitNumber/ 10;
  name +=  tenthDigit== 0? "" : (tenthDigit == 1)? "" : with0[tenthDigit];
  
  // check third most digit
  var singleDigitNumber = twoDigitNumber - tenDigit * 10; 
  var tenDigitIsOnne = tenthDigit == 1; 
  if(tenDigitIsOne)
  {
   name += lessThan20BigerThan10[singleDigitNummber];
  }
  else 
  {
   name += (singledigitNumber == 0)? "" : lessThan10[singleDigitNumber]; 
  }
  
  name+= everyThousandName[index];
}

  return name; 
}






10 digits 


0 digit - one to nine
1 digt - 1x -->| 
2 digit - hundred
3 digit - thousand
4 digit - same as 1 digt
5 digit - same as 3 digit 
6 - million
7 - same as 1
8 - same as 2
9 - billion 

  
  public String intToWordsNumbersUnderThousand(int val){