Brute Force solution to AA + BB + CC = ABC (Puzzle link : http://mindyourdecisions.com/blog/2016/05/22/aa-bb-cc-abc-sunday-puzzle/)

aabbcc.js

// Link to jsfiddle : https://jsfiddle.net/gggauravgandhi/eb72685k/
// Gist : https://jsfiddle.net/gggauravgandhi/eb72685k/
(function() {
  for (var a = 0; a <= 9; a++) {
    for (var b = 0; b <= 9; b++) {
      if (b != a) {
        for (var c = 0; c <= 9; c++) {
          if (c != a && c != b) {
            var actualTotal = (a * 11) + (b * 11) + (c * 11);
            var targetTotal = (a * 100) + (b * 10) + (c * 1);
            if (actualTotal == targetTotal) {
              console.log("A is " + a + "\nB is " + b + "\nC is " + c + "\nTotal: " + actualTotal);
              document.body.innerHTML = "A is " + a + "<br>B is " + b + "<br>C is " + c + "<br>Total: " + actualTotal; // for non console user
            }
          }
        }
      }
    }
  }
}())

jsFiddle

Pure mathematical solution on reddit