Advent of Code 2018: day 2 (part 1)

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    d3.tsv('input.tsv', function(error, input) {
  		if (error) throw error;
     
       console.log(calcChecksum(input))
       
      function calcChecksum(data){
        var sum1 = 0;
        var sum2 = 0;
        
         data.forEach(string => {
           sum1 = sum1 + calcRep(string.input, 2)
           sum2 = sum2 + calcRep(string.input, 3)
         })
        
         return sum1 * sum2;
        
      }
      
      // returns 1 if string contains a
      //character that repeats exactly rep times
      function calcRep(string, rep){
        
        var stringArr = string.split('')
        var pastCharsArr = []
        console.log("String: " + string)
        
        for(var i = 0; i < stringArr.length - 1; i++){
          var counter = 1;
          
          for(var j = i + 1; j < stringArr.length; j++){
            if(!pastCharsArr.find(item => item === stringArr[i]) && stringArr[i] === stringArr[j]){
              console.log(stringArr[j])
              counter++;
              console.log(counter)
            }
          }
          if (counter === rep) {
            		console.log("Found rep: " + rep)
                return 1
              }
       pastCharsArr.push(stringArr[i])
        }
return 0;        
      }
      
    });

</script>
</body>

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