Add new course

BM40A1500 Data Structures and Algorithms/Assignments/Week 7/quicksort.py

@@ -0,0 +1,24 @@
+def qsort(A, i, j):
+    if i >= j:
+        return
+    p = partition(A, i, j)
+    qsort(A, i, p-1)
+    qsort(A, p+1, j)
+
+
+def partition(A, i, j):
+    pivot = A[j]
+    p = i
+    for q in range(i, j):
+        if A[q] < pivot:
+            A[p], A[q] = A[q], A[p]
+            p += 1
+    A[p], A[j] = A[j], A[p]
+    return p
+
+
+if __name__ == "__main__":
+    A = [9, 7, 1, 8, 5, 3, 6, 2, 4]
+    print(A)    # [9, 7, 1, 8, 5, 3, 6, 2, 4]
+    qsort(A, 0, len(A)-1)
+    print(A)    # [1, 2, 3, 4, 5, 6, 7, 8, 9]