Merge pull request #594 from badmojo76/kth_largest_element

Kth largest element

Author: probot-auto-merge[bot]

Python/kth_element.py

@@ -0,0 +1,35 @@
+#!/usr/bin/python3
+
+# Usage:  kth_element(place_of_element,largest_or_smallest,array)
+# If you are looking for the 3rd largest element of "myarray": kth_element(3,'largest',myarray)
+
+def kth_element(k,large_or_small,mylist):
+
+    if large_or_small == "largest":
+        modifier = 1
+    elif large_or_small == "smallest":
+        modifier = -1
+    else:
+        print("Valid values for the sort are 'largest' or 'smallest'")
+        exit(1)
+
+    if len(mylist) < k or k < 1:
+        print("ERROR: Array size is " + str(len(mylist)) + ", but requested value is " + str(k) + "...")
+        return None
+
+    newlist = [None] * k
+
+    while len(mylist) > 0:
+        test = mylist.pop()
+        for i in range(0,k):
+            if newlist[i] == None or test * modifier > newlist[i] * modifier:
+                newlist.insert(i,test)
+                newlist.pop()
+                #print(newlist)  # Uncomment to see the value list build in action
+                break
+
+    return(newlist[k-1])
+
+if __name__ == "__main__":
+    mylist = [ 42, 39, 857, 20, 3884, 82, 0, 84, 8, 3, -50, -1000 ]
+    print(kth_element(1,'smallest',mylist))