Simple digit code breaker

function tryCode(indications) {
  if(!indications)
    return proposition;
    
  var a = proposition[0], b = proposition[1], c = proposition[2];
  
  if(indications[0] > 0)
    a++;
  if(indications[1] > 0)
    b++;
  if(indications[2] > 0)
    c++;
  
  proposition = [a, b, c];
  return proposition;
}

var proposition = [0, 0, 0];