new

Python/sorting/bubble_sort.py

@@ -0,0 +1,14 @@
+from collections import Counter
+
+def bubble_sort(arr, freq):
+    n = len(arr)
+    for i in range(n):
+        for j in range(0, n-i-1):
+            if (freq[arr[j]], -arr[j]) < (freq[arr[j+1]], -arr[j+1]):
+                arr[j], arr[j+1] = arr[j+1], arr[j]
+
+if __name__ == "__main__":
+    arr = [4,6,2,4,3,2,2,6]
+    freq = Counter(arr)
+    bubble_sort(arr,freq)
+    print(arr)

Python/sorting/selection_sort.py

@@ -0,0 +1,16 @@
+from collections import Counter
+
+def selection_sort(arr, freq):
+    n = len(arr)
+    for i in range(n):
+        max_idx = i
+        for j in range(i+1, n):
+            if (freq[arr[j]], -arr[j]) > (freq[arr[max_idx]], -arr[max_idx]):
+                max_idx = j
+        arr[i], arr[max_idx] = arr[max_idx], arr[i]
+
+if __name__ == "__main__":
+    arr = [4,6,2,4,3,2,2,6]
+    freq = Counter(arr)
+    selection_sort(arr,freq)
+    print(arr)

Python/sorting/shell_sort.py

@@ -0,0 +1,20 @@
+from collections import Counter
+
+def shell_sort(arr, freq):
+    n=len(arr)
+    gap=n//2
+    while gap>0:
+        for i in range(gap,n):
+            temp=arr[i]
+            j=i
+            while j>=gap and (freq[arr[j-gap]],-arr[j-gap])<(freq[temp],-temp):
+                arr[j]=arr[j-gap]
+                j-=gap
+            arr[j]=temp
+        gap//=2
+
+if __name__=="__main__":
+    arr=[4,6,2,4,3,2,2,6]
+    freq=Counter(arr)
+    shell_sort(arr,freq)
+    print(arr)