Add ability for user to select algorithm

main.py

@@ -337,7 +337,14 @@ def simplex():
 if __name__ == '__main__':
     logger.info('Starting program.')
 
-    ford_fulkerson()
-    simplex()
+    logger.info('Choose an option:')
+    logger.info('   1) Solve Maximum Flow via Ford Fulkerson.')
+    logger.info('   2) Solve Maximum Flow via Simplex.')
+
+    user_input = str(input()).strip()
+    if user_input == '1':
+        ford_fulkerson()
+    elif user_input == '2':
+        simplex()
 
     logger.info('Terminating program.')