play_with_lists_and_dicts - day 9

Author: vladlind

days/07-09-data-structures/code/play_with_lists_and_dicts.py

@@ -0,0 +1,45 @@
+from data import us_state_abbrev, states_list
+
+NOT_FOUND = 'N/A'
+
+def get_every_nth_state(states=states_list, n=10):
+    """Return a list with every nth item (default argument n=10, so every
+       10th item) of the states list above (remember: lists keep order)"""
+    return [states[i] for i in range(n-1,50,n)]
+
+
+def get_state_abbrev(state_name, us_state_abbrev=us_state_abbrev):
+    """Look up a state abbreviation by querying the us_state_abbrev
+       dict by full state name, for instance 'Alabama' returns 'AL',
+       'Illinois' returns 'IL'.
+       If the state is not in the dict, return 'N/A' which we stored
+       in the NOT_FOUND constant (takeaway: dicts are great for lookups)"""
+    try:
+        return us_state_abbrev.pop(state_name)
+    except KeyError:
+        return NOT_FOUND
+
+
+def get_longest_state(data):
+    """Receives data, which can be the us_state_abbrev dict or the states
+       list (see above). It returns the longest state measured by the length
+       of the string"""
+    return sorted(data, key=len,reverse=True)[0]
+        
+
+
+def combine_state_names_and_abbreviations(us_state_abbrev=us_state_abbrev,
+                                          states=states_list):
+    """Get the first 10 state abbreviations ('AL', 'AK', 'AZ', ...) from
+       the us_state_abbrev dict, and the last 10 states from the states
+       list (see above) and combine them into a new list without losing
+       alphabetical order"""
+    return sorted(us_state_abbrev.values())[:10]+(sorted(states)[-10:])
+
+if __name__ == "__main__":
+    
+    print([(k,v) for k,v in us_state_abbrev.items()][9])
+    print(states_list[9])
+    print([k for k in us_state_abbrev.keys()][44])
+    print([v for v in us_state_abbrev.values()][26])
+