Add odds util functions

util/odds.py

@@ -0,0 +1,65 @@
+"""
+    util/odds.py
+
+    Calculate the odds of winning a lottery game
+"""
+
+from math import comb
+
+
+def calculate_odds(pool_size: int, draw_count: int) -> int:
+    """
+    Calculate the total number of possible combinations in a set of numbers with a specific draw count.
+
+    :param pool_size: Total count of numbers in the pool
+    :param draw_count: The count of numbers to draw from the pool
+    :return: The total number of possible combinations
+
+    Example:
+        If a lottery game has a main ball pool of 49 numbers from which 5 numbers are drawn and a pool of
+        18 numbers from which 1 number is drawn (game ball), calculate the odds of winning that game.
+
+        >>> calculate_odds(pool_size=49, draw_count=5)
+        1906884
+        >>> calculate_odds(pool_size=18, draw_count=1)
+        18
+    """
+
+    if draw_count < 0 or draw_count > pool_size:
+        raise ValueError('Integer values must be positive and draw counts must be less than pool size.')
+    total_combinations = comb(pool_size, draw_count)
+    return total_combinations
+
+
+def get_odds_of_winning(
+        main_ball_draw_pool: int,
+        main_ball_draw_count: int,
+        game_ball_draw_pool: int,
+        game_ball_draw_count: int
+) -> str:
+    """
+        Calculate the odds of winning a specific lottery game with one draw
+
+        :param main_ball_draw_pool: Total count of numbers in the main ball pool
+        :param main_ball_draw_count: The count of numbers to draw from the main ball pool
+        :param game_ball_draw_pool: Total count of numbers in the game ball pool
+        :param game_ball_draw_count: The count of numbers to draw from the game ball pool
+
+        :return: The odds of winning a specific lottery game with one draw
+
+        Example:
+            To calculate the odds of winning a lottery game with 5 numbers drawn from a main ball pool of 49 and
+            1 number drawn from a game ball pool of 19 numbers.
+
+            >>> get_odds_of_winning(main_ball_draw_pool=49, main_ball_draw_count=5, game_ball_draw_pool=18, game_ball_draw_count=1)
+            'The odds of winning are 1 in 34,323,912'
+    """
+
+    if (main_ball_draw_count < 0 or main_ball_draw_count > main_ball_draw_pool or
+            game_ball_draw_count < 0 or game_ball_draw_count > game_ball_draw_pool):
+        raise ValueError('Integer values must be positive and draw counts must be less than pool size.')
+
+    main_ball_odds = calculate_odds(main_ball_draw_pool, main_ball_draw_count)
+    game_ball_odds = calculate_odds(game_ball_draw_pool, game_ball_draw_count)
+
+    return f"The odds of winning are 1 in {main_ball_odds * game_ball_odds:,}"