var start2003 = ee.Date('2003-05-01');
var finish2003 = ee.Date('2003-06-01');

var start2004 = ee.Date('2004-05-01');
var finish2004 = ee.Date('2004-06-01');

var start2005 = ee.Date('2005-05-01');
var finish2005 = ee.Date('2005-06-01');


var start2006 = ee.Date('2006-05-01');
var finish2006 = ee.Date('2006-06-01');

var start2007 = ee.Date('2007-05-01');
var finish2007 = ee.Date('2007-06-01');

var start2008 = ee.Date('2008-05-01');
var finish2008 = ee.Date('2008-06-01');

var start2009 = ee.Date('2009-05-01');
var finish2009 = ee.Date('2009-06-01');

var start2010 = ee.Date('2010-05-01');
var finish2010 = ee.Date('2010-06-01');

var start2011 = ee.Date('2011-05-01');
var finish2011 = ee.Date('2011-06-01');

var start2012 = ee.Date('2012-05-01');
var finish2012 = ee.Date('2012-06-01');


var start2013 = ee.Date('2013-05-01');
var finish2013 = ee.Date('2013-06-01');

var start2014 = ee.Date('2014-05-01');
var finish2014 = ee.Date('2014-06-01');

var start2015 = ee.Date('2015-05-01');
var finish2015 = ee.Date('2015-06-01');

var start2016 = ee.Date('2016-05-01');
var finish2016 = ee.Date('2016-06-01');

var start2017 = ee.Date('2017-05-01');
var finish2017 = ee.Date('2017-06-01');

var start2018 = ee.Date('2018-05-01');
var finish2018 = ee.Date('2018-06-01');


var l8filtered = l8raw.filterDate(start2018, finish2018)
                      .filterBounds(caoxian);

Map.centerObject(l8filtered, 10);



var landsat = ee.Algorithms.Landsat.simpleComposite({
  collection: l8filtered,
  asFloat: true
});

Map.addLayer(landsat, {bands: ['B4', 'B3', 'B2'], max: 0.2}, 'composite');
Map.addLayer(landsat, {bands: ['B7', 'B5', 'B4'], max: 0.5}, 'SWIR-NIR-R');

var trainingFeatures = water.merge(grass).merge(cropland).merge(urban);

var predictionBands = ['B2', 'B3', 'B4', 'B5', 'B6', 'B7', 'B10', 'B11'];

var classifierTraining = landsat.select(predictionBands)
    .sampleRegions({
      collection: trainingFeatures,
      properties: ['class'],
      scale: 30
    });


    var classifier = ee.Classifier.cart().train({
      features: classifierTraining,
      classProperty: 'class',
      inputProperties: predictionBands
    });


var classified = landsat.select(predictionBands).classify(classifier);


Map.addLayer(classified, {min: 0, max: 3, palette: ['red', 'blue', 'yellow', 'cyan']}, 'classified');