adding a script to look for words with euclidean distance of 1.

diff_by_one.py

@@ -0,0 +1,28 @@
+"""
+diff_by_one.py
+
+Donald Knuth
+Art of Computer Programming 
+Volume 4 Facsimile 0
+Exercise #28
+
+Find pairs of SGB word vectors that differ by +/-1.
+"""
+from get_words import get_words
+from euclidean_distance import euclidean_distance
+
+if __name__=="__main__":
+    words = get_words()
+    #words = words[:1000]
+
+    k = 0
+    off_by_one = []
+    for i in range(len(words)):
+        for j in range(i,len(words)):
+            d = euclidean_distance(words[i],words[j])
+            if(abs(d)==1):
+                k += 1
+                off_by_one.append((words[i],words[j]))
+                print("{0:s}, {1:s}".format(words[i],words[j]))
+
+    print("{0:d} words have a Euclidean distance of +/-1.".format(k))