Merge bdfb929698 into fcf82a1eda

data_structures/arrays/sliding_window.py

@@ -0,0 +1,53 @@
+"""
+Given an array of both positive and negative integers, the task is to compute sum of minimum and maximum elements of all sub-array of size k.
+
+https://www.geeksforgeeks.org/sum-minimum-maximum-elements-subarrays-size-k/
+"""
+
+
+# this function will return sum of min and max of the window
+def get_min_max(array: list, start: int, end: int) -> int:
+    max = min = array[start]
+
+    for i in range(start + 1, end + 1):
+        if array[i] < min:
+            min = array[i]
+        if array[i] > max:
+            max = array[i]
+
+    return max + min
+
+
+def sum(array: list, size: int, k: int) -> int:
+    """
+    Args:
+        array (list): the input array
+        size (int): size of the array
+        k (int): size of the sub-array
+
+    Returns:
+        int : sum of the minimum and maximum elements of all sub-arrays of size-k
+    """
+    """
+        Examples:
+        >>> sum([2, 5, -1, 7, -3, -1, -2], 7 ,4)
+        18
+    """
+    # create first window of size k
+    start, end = 0, k - 1
+    result = 0
+    # get the minimum and maximum element from the window and add it to the result
+    result += get_min_max(array, size, start, end)
+
+    while start < size - k and end < size:
+        start += 1
+        end += 1
+        result += get_min_max(array, start, end)
+
+    return result
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()