Improved readability (#1615)

* improved readability

* further readability improvements

* removed csv file and added f

dynamic_programming/knapsack.py

@@ -81,13 +81,13 @@ def knapsack_with_example_solution(W: int, wt: list, val: list):
         raise ValueError(
             "The number of weights must be the "
             "same as the number of values.\nBut "
-            "got {} weights and {} values".format(num_items, len(val))
+            f"got {num_items} weights and {len(val)} values"
         )
     for i in range(num_items):
         if not isinstance(wt[i], int):
             raise TypeError(
                 "All weights must be integers but "
-                "got weight of type {} at index {}".format(type(wt[i]), i)
+                f"got weight of type {type(wt[i])} at index {i}"
             )
 
     optimal_val, dp_table = knapsack(W, wt, val, num_items)