ther is no data in the common folder!

[wangjiangchuan]

images = loadMNISTImages('../common/train-images-idx3-ubyte');

when I run the cnnExercise.m, gives the following error:
error usage loadMNISTImages (line 6)
Could not open ../common/train-images-idx3-ubyte
error cnnExercise (line 26)
images =
loadMNISTImages('../common/train-images-idx3-ubyte');

[Yannic92]

Please read all three sentences: http://ufldl.stanford.edu/tutorial/StarterCode/