Why I can't loop this function?-CodePudding

My teacher gave us a lesson where we had to find out how many times a x number was drawn in the lottery. He gave us a .txt document containing all datas from the previous years. He told us to build a function to discover these values. I ended up with this:

//Transfer the txt logs to variable 'conteudo'

try {
  conteudo = fs.readFileSync("dados.txt", "utf8");
  conteudo = conteudo.split("\r\n");
  vezessort = 0;
} catch(erro) {
  console.error(erro.message);
}

//Function created to review all the lines in the txt file
//First for loop is to split each line, making them an array
//Second loop is to compare the values 2 to 7 on each line, where contains the numbers drawn in the lottery

function vezSort(a){
  for (i = 1; i < conteudo.length; i  ){
    conteudo[i] = conteudo[i].split(";");
    for(j = 2; j < 8; j  ){
      if(conteudo[i][j] == a){
        vezessort  = 1;
      }
    }
  }
}

//In this exercise we need to capture the input from user, and use it as a parameter on the function

a = parseInt(prompt('Digite um número: '));
r = vezSort(a);
console.log(`O número foi sorteado ${vezessort} vezes.`);

It works perfectly, the final values matches with the desired output he gave. The problem is, in the next question he tell us to loop the function for each number between 1 to 60. But every attempt I try to loop I get problems with this line: conteudo[i] = conteudo[i].split(";");. What I am doing wrong? (Btw, in this exercise the input from the user is not needed.)

CodePudding user response：

The problem is that you're modifying the conteudo array when you call vezSort(). It's initially an array of strings, but you're changing it to a 2-dimensional array when you do conteudo[i] = conteudo[i].split(";");

You should either convert it to a 2-dimensional array just once, outside the vezSort() function, or use a local variable rather than modifying the original array.

Doint it once is more efficient, so that's how I show it:

try {
  conteudo = fs.readFileSync("dados.txt", "utf8");
  conteudo = conteudo.split("\r\n");
  conteudo = conteudo.map(line => line.split(';'));
  vezessort = 0;
} catch(erro) {
  console.error(erro.message);
}

//Function created to review all the lines in the txt file
//First for loop is to split each line, making them an array
//Second loop is to compare the values 2 to 7 on each line, where contains the numbers drawn in the lottery

function vezSort(a){
  for (i = 1; i < conteudo.length; i  ){
    for(j = 2; j < 8; j  ){
      if(conteudo[i][j] == a){
        vezessort  = 1;
      }
    }
  }
}

CodePudding user response：

.split() turns a string into an array of substrings, not an array into a string. For that, use .join().

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/join