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Loop not working.

var userCity=prompt("what city are you from?")
var numElements = cleanestCities.length;
var matchFound = false;
var cleanestCities = ["Louisville", "New York", "Mexico City", "Japan"];
for (var i=0; i<numElements; i++) {
  if(userCity === cleanestCities[i]) {
    matchFound = true;
    alert("it's one of the cleanest cities")
if (matchFound) ===false) {
  alert("It's not on the list");

what am i doing wrong?

It looks like you have an extra parenthesis in this line: if (matchFound) ===false) {. Remove the one after the matchFound.

I just dont understand why the prompt does not pop.

3 Answers

Steven Parker
Steven Parker
229,920 Points

:point_right: There's a couple of issues preventing your code from running:

  • On line 2, you reference cleanestCities before it has been declared. Place this line after that is done.
  • On line 12, you have a stray closing parenthesis, as Jeremy indicated.

Optionally, you could condense line 12 to this:

if (!matchFound) {

place a ';' at the end of that line.

Steven Parker
Steven Parker
229,920 Points

:information_source: Semicolons at the end of a line are good practice, but they are completely optional.

Sean T. Unwin
Sean T. Unwin
28,690 Points

The variable, var numElements = cleanestCities.length; needs to be after cleanestCities has been declared. Unmatched closing parenthesis at if (matchFound) ===false) {.