Next 0-Z Sequence Code with Javascript

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Next 0-Z Sequence Code with Javascript

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#1 by (3 votes)
#2 by (2 votes)

2

I need to create a JavaScript function that gets a string of letters and numbers and it returns the next count value. The count goes from 0 to Z. Sequence example:

0 - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - A - B - C - D Y - Z - 01 - 02 - 03 [...] - 0Z - 10 - 11 - 12 [...]

Function example:

nextCode ("AF10") // Return "AF11"

nextCode ("A4ZZ") // Return "A500"

What I've tried so far:

/*Gerar Novo Código*/
function nextCode(lastCode){
    //Verifica o Tamanho
    var codeSize = lastCode.length;
    //Verifica o index do ultimo caracter
    var indexLastValidChar = codeSize-1;
    //Se o ultimo caracter for igual a Z pega o caractere anterior (loop)
    var loopAtive;
    do {
        indexLastValidChar = loopAtive == true ?  indexLastValidChar-1 :indexLastValidChar;
        var lastValidChar = lastCode.substr(indexLastValidChar, 1);
        loopAtive = true;
    } while(lastValidChar == "Z");
    //Pega a primeira metade do novo código
    var firstHalfCode = lastCode.slice(0, indexLastValidChar);
    //Verifica se o ultimo caracter diferente de Z é numero ou letra
    var isChar = isNaN(parseInt(lastValidChar));
    //Se for char, gera o próximo caracter
    var newChar;
    if (isChar){
        newChar = String.fromCharCode(lastValidChar.charCodeAt(0)+1);
    } //Se não for, verifica se o número é 9
    else if (lastValidChar == "9") {
        newChar = "A";
    }  //Se não for, adicona um ao número
    else {
        newChar = parseInt(lastValidChar) + 1;
    }
    //Junta primeira metade
    firstHalfCode = firstHalfCode + newChar;
    //Adicona zeros ao final, caso codeSize seja diferente de indexLastValidChar+1 - ou seja, existem Zs
    for (var i = 0; i < codeSize - indexLastValidChar+1; i++) {
        var newCode = firstHalfCode + 0;
    }
    //Mostra o novo código
    console.log(newCode);
}
nextCode ("AF10");
nextCode ("A4ZZ");

The results do not work out and I'm kind of lost ...

javascript

asked by anonymous 30.07.2017 / 04:53

2 answers

3

By understanding the question, it appears that it is willing to work with a base 36, but the sequence example described in the question does not fall right at base 36. Examples of sequences of "AF10" - > "AF11" and "A4ZZ" - > "A500" are correct, but following base 36 the number after "Z" would be "10". If this is the case, simply use the parseInt and String.prototype.toString functions, which allow you to pass the base by parameter.

var nextCode = function(number) {
  var inBase10 = parseInt(number, 36);
  return (inBase10 + 1).toString(36).toUpperCase();
};

nextCode('AF10'); // => "AF11"
nextCode('A4ZZ'); // => "A500"

30.07.2017 / 09:37

include with parameter? Why is not it good to use this function and how do I identify the user's IP then?

score 2 · Accepted Answer

If you know String that you have characters you can use a loop to make these changes / increments. Using flags to steer it should increase.

Suggestion:

var Next = (function(seq) {
  var lastChar = seq.slice(-1);

  return function(str) {
    if (!str) return '0';
    var chars = str.split('');
    var raize = true,
      addChar = false;
    for (var i = chars.length - 1; i + 1; i--) {
      var charIndex = seq.indexOf(chars[i]);
      if(!raize) continue;
      if (chars[i] !== lastChar) {
        if (!raize) break;
        chars[i] = seq[charIndex + 1];
        raize = false;
      } else {
        chars[i] = seq[0];
        raize = true;
        if (raize && i == 0) chars.unshift(seq[0]);
      }
    }
    return chars.join('');
  }

})('0123456789ABCDEFGHIJKLMNOPQRSTUVXYZ');

['', '00', '0Z', 'ZZ', 'AF10', 'A4ZZ', 'A4Z0'].forEach(test => console.log(test, Next(test)));