why does it returns '-1' instead of the index of the index jQuery

Question

I'm running a 'for' loop to check if the elements in the winOptions array are in the oneNums array. However, every time I use indexOf property it sends back -1 even if the number is in the oneNums array. Is it possible it returns that because ['1','2'] is different that [1,2] ? How can I fix this.

I have this variables:

 var oneNums = [];
 var winOptions = [[1,2,3],[4,5,6],[7,8,9],[1,5,9],[3,5,9],[1,4,7],[2,5,8],[3,6,9]];
 var a;

And this jQuery function:

$('.btn-xo').click(function(){
  if (turn === 'one'){
    $(this).text(pickOne);
    $(this).prop('disabled', true);
    oneNums.push($(this).val());
    oneNums.sort(function(a, b){
      return a - b;
    });
    for(var i = 0; i < winOptions.length; i++){
      for(var j = 0; j < winOptions[i].length; j++){
        a = oneNums.indexOf(winOptions[i][j]);
        if (a === -1){
          p1 = [];
          break;
        } else {
          p1.push(oneNums[a]);
          console.log('aca');
        }
      }
    }
    console.log(a);
    turn = 'two';
    count += 1;        
  }

Answer 1

indexOf string with number will fail. So, change number to string

First convert number to String, using .toString()

for(var i = 0; i < winOptions.length; i++){
      for(var j = 0; j < winOptions[i].length; j++){
        a = oneNums.indexOf((winOptions[i][j]).toString());
        if (a === -1){
          p1 = [];
          break;
        } else {
          p1.push(oneNums[a]);
          console.log('aca');
        }
      }
    }

Check these two examples,

['1','2'].indexOf(1); o/p ===> -1

['1','2'].indexOf((1).toString()); o/p ===> 0