Shell Sort for beginners

python basics/ADVANCE_HEAPSORT.py

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+# This code is contributed by Pranav Jain 
+
+def heapify(arr, n, i): 
+    largest = i  # Initialize largest as root 
+    l = 2 * i + 1     # left = 2*i + 1 
+    r = 2 * i + 2     # right = 2*i + 2 
+
+
+    if l < n and arr[i] < arr[l]: 
+        largest = l 
+
+
+    if r < n and arr[largest] < arr[r]: 
+        largest = r 
+
+    # Change root, if needed 
+    if largest != i: 
+        arr[i],arr[largest] = arr[largest],arr[i]  # swap 
+
+        # Heapify the root. 
+        heapify(arr, n, largest) 
+
+# The main function to sort an array of given size 
+def heapSort(arr): 
+    n = len(arr) 
+
+
+    for i in range(n, -1, -1): 
+        heapify(arr, n, i) 
+
+
+    for i in range(n-1, 0, -1): 
+        arr[i], arr[0] = arr[0], arr[i]   # swap 
+        heapify(arr, i, 0) 
+
+
+arr = [ 12, 11, 13, 5, 6, 7] 
+heapSort(arr) 
+n = len(arr) 
+print ("Sorted array is") 
+for i in range(n): 
+    print ("%d" %arr[i]), 

python basics/PrimeNo_interval.py

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+startRange = 11
+endRange = 25
+
+for val in range(startRange, endRange + 1): 
+
+   if val > 1: 
+       for n in range(2, val): 
+           if (val % n) == 0: 
+               break
+       else: 
+           print(val) 

python basics/basicShellSort.py

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+def shellSort(arr): 
+
+
+    n = len(arr) 
+    gap = n/2
+
+
+    # The first gap elements a[0..gap-1] are already in gapped  
+    # order keep adding one more element until the entire array 
+    # is gap sorted 
+    while gap > 0: 
+
+        for i in range(gap,n): 
+
+            # add a[i] to the elements that have been gap sorted 
+            # save a[i] in temp and make a hole at position i 
+            temp = arr[i] 
+
+            # shift earlier gap-sorted elements up until the correct 
+            # location for a[i] is found 
+            j = i 
+            while  j >= gap and arr[j-gap] >temp: 
+                arr[j] = arr[j-gap] 
+                j -= gap 
+
+            # put temp (the original a[i]) in its correct location 
+            arr[j] = temp 
+        gap /= 2
+
+
+
+arr = [ 12, 34, 54, 2, 3] 
+
+n = len(arr) 
+print ("Array before sorting:") 
+for i in range(n): 
+    print(arr[i]), 

python basics/fibonacci_dp.py

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+FibArray = [0,1] 
+
+def fibonacci(n): 
+    if n<0: 
+        print("Incorrect input") 
+    elif n<=len(FibArray): 
+        return FibArray[n-1] 
+    else: 
+        temp_fib = fibonacci(n-1)+fibonacci(n-2) 
+        FibArray.append(temp_fib) 
+        return temp_fib 
+
+# Driver Program 
+
+print(fibonacci(9))