Baisal ergeshev

src/iterative_sorting/iterative_sorting.py

@@ -1,30 +1,42 @@
-# TO-DO: Complete the selection_sort() function below 
+# TO-DO: Complete the selection_sort() function below
 def selection_sort( arr ):
     # loop through n-1 elements
     for i in range(0, len(arr) - 1):
-        cur_index = i
-        smallest_index = cur_index
-        # TO-DO: find next smallest element
-        # (hint, can do in 3 loc) 
-
-
-
-
-        # TO-DO: swap
-
-
-
-
+        cur_index = i#establishes first index
+        for j in range(i+1, len(arr)):#the array besides the first
+            if arr[cur_index] > arr[j]:# if the first is greater than anything
+                cur_index = j#new starting point
+        arr[i], arr[cur_index] = arr[cur_index], arr[i]
     return arr
 
-
+list = [1, 5, 8, 4, 2, 9, 6, 0, 3, 7]
 # TO-DO:  implement the Bubble Sort function below
 def bubble_sort( arr ):
-
+    swapped = True
+    while swapped:
+        swapped = False
+        for i in range(len(arr)-1):
+            if arr[i] > arr[i+1]:
+                arr[i],arr[i+1] = arr[i+1],arr[i]
+                swapped = True
     return arr
 
 
+
+
 # STRETCH: implement the Count Sort function below
 def count_sort( arr, maximum=-1 ):
-
-    return arr
+    # first is to tally all of the occurances of each number and make an array that is ordered by index of all numbers 0-9
+    # second is to add the tally number to the next number in the line
+    count_index = [0,0,0,0,0,0,0,0,0,0]
+    for i in range(len(arr)):#tally occurances
+        count_index[arr[i]] += 1
+    for i in range(len(count_index)):#add the previous number to the next number
+        count_index[i] = count_index[i]+count_index[i-1]
+    count_index.pop()
+    count_index.insert(0,0)#shift all numbers to the right
+    output_arr = [0]*len(arr)
+    for i in range(len(arr)):#populate output array
+        output_arr[count_index[arr[i]]] = arr[i]
+        count_index[arr[i]]+=1
+    return output_arr

src/recursive_sorting/rec.py

@@ -0,0 +1,7 @@
+
+def greet(n):
+    if n  == 1:
+        return 1
+    return n * greet(n - 1)
+
+

src/recursive_sorting/recursive_sorting.py

@@ -1,33 +1,63 @@
 # TO-DO: complete the helpe function below to merge 2 sorted arrays
+
 def merge( arrA, arrB ):
-    elements = len( arrA ) + len( arrB )
-    merged_arr = [0] * elements
-    # TO-DO
-
-    return merged_arr
+    result = []
+    i = j = 0
+    while i < len(arrA) and j < len(arrB):
+        if arrA[i] < arrB[j]:
+            result.append(arrA[i])
+            i+=1
+        else:
+            result.append(arrB[j])
+            j+=1
+    result += arrA[i:]
+    result += arrB[j:]
+
+
+    return result
 
+#arrA = [2,3,4,5,6,7]
+#arrB = [9,10,11,12,13]
+#merge(arrA, arrB)
 
 # TO-DO: implement the Merge Sort function below USING RECURSION
 def merge_sort( arr ):
-    # TO-DO
+    #(base case) if the array is empty or lenght 1 return
+    if len(arr) <= 1:
+        return arr
+        left = merge_sort(arr[:len(arr)//2])
+        right = merge_sort(arr[len(arr)//2:])
+        arr = merge(left, right)
 
     return arr
+arr = [2,5,3,6,9,4,15,0]
+merge_sort(arr)
+    # TO-DO
+
+# TO-DO: implement the Merge Sort function below USING RECURSION
+def merge_sort( arr ):
+
+    #split here
+
+    #find the middle of arr
+    #put stuff to the left in left
+    #put the stuff to the right in right
 
+    #merge left and right
 
-# STRETCH: implement an in-place merge sort algorithm
-def merge_in_place(arr, start, mid, end):
+# # STRETCH: implement an in-place merge sort algorithm
+#def merge_in_place(arr, start, mid, end):
     # TO-DO
 
-    return arr
+   # return arr
 
-def merge_sort_in_place(arr, l, r): 
+#def merge_sort_in_place(arr, l, r):
     # TO-DO
 
-    return arr
+    #return arr
 
 
-# STRETCH: implement the Timsort function below
-# hint: check out https://github.com/python/cpython/blob/master/Objects/listsort.txt
-def timsort( arr ):
+# # STRETCH: implement the Timsort function below
+#def timsort( arr ):
 
-    return arr
+    #return arr

src/recursive_sorting/test_recursive.py

@@ -32,4 +32,4 @@ def test_merge_sort(self):
 
 
 if __name__ == '__main__':
-    unittest.main()
+    unittest.main()