Merge pull request BeeBombshell#1 from BeeBombshell/main

Updating

Author: JASKAMAL22

Backtracking/Knights_tour.py

@@ -0,0 +1,23 @@
+def knights_tour(n, row, col):
+    visited = [[False]*n for i in range(n)]
+    res = []
+    def path_gen(path,r,c,visited,step):
+        if r < 0 or c < 0 or r >= n or c >= n or visited[r][c]:
+            return
+        if step == n*n:
+            res.append(path + f'({r},{c})')
+            return   
+        visited[r][c] = True
+        path_gen(path + f'({r},{c}) ', r - 2, c + 1, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r - 2, c - 1, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r - 1, c + 2, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r - 1, c - 2, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r + 2, c + 1, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r + 2, c - 1, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r + 1, c + 2, visited, step+1)
+        path_gen(path + f'({r},{c}) ', r + 1, c - 2, visited, step+1)
+        visited[r][c] = False
+    path_gen('', row, col,visited,1)
+    return res
+
+print(knights_tour(5, 2, 2))

Backtracking/N_queens.py

@@ -0,0 +1,26 @@
+def n_queens(n):
+    res = []
+    board = [['.']*n for i in range(n)]
+    cols = set()
+    pdiags = set()
+    ndiags = set()
+    def gen(r):
+        if r == n:
+            res.append([''.join(row) for row in board])
+            return
+        for c in range(n):
+            if c in cols or r+c in pdiags or r-c in ndiags:
+                continue
+            board[r][c] = 'Q'
+            cols.add(c)
+            pdiags.add(r+c)
+            ndiags.add(r-c)
+            gen(r + 1)
+            board[r][c] = '.'
+            cols.remove(c)
+            pdiags.remove(r+c)
+            ndiags.remove(r-c)
+    gen(0)
+    return res
+
+print(n_queens(8))

DSA/Queue_using_list.py

@@ -0,0 +1,31 @@
+# Implement Queue using List(Functions)
+q=[]
+def Enqueue():
+    if len(q)==size: # check wether the stack is full or not
+        print("Queue is Full!!!!")
+    else:
+        element=input("Enter the element:")
+        q.append(element)
+        print(element,"is added to the Queue!")
+def dequeue():
+    if not q:# or if len(stack)==0
+        print("Queue is Empty!!!")
+    else:
+        e=q.pop(0)
+        print("element removed!!:",e)
+def display():
+    print(q)
+    size=int(input("Enter the size of Queue:"))
+    while True:
+        print("Select the Operation:1.Add 2.Delete 3. Display 4. Quit")
+        choice=int(input())
+        if choice==1:
+            Enqueue()
+        elif choice==2:
+            dequeue()
+        elif choice==3:
+            display()
+        elif choice==4:
+            break
+        else:
+            print("Invalid Option!!!")

README.md

@@ -37,6 +37,7 @@ The following topics will be elaborated:
   * Linear Search
   * Binary Search
 * Recursion
+  * Ackermann Function
 * Backtracking
 * Dynamic Programming
 * Linked List

Recursion/Ackermann.py

@@ -0,0 +1,10 @@
+def Ackermann(m, n):
+    if m == 0:
+        return n + 1
+    elif m > 0 and n == 0:
+        return Ackermann(m - 1, 1)
+    else:
+        return Ackermann(m - 1, Ackermann(m, n - 1))     
+m = int(input())
+n = int(input())          
+print(Ackermann(m, n))        

Recursion/is_Palindrome.py

@@ -0,0 +1,16 @@
+'''A recursive Python program to check whether a string is palindrome or not'''
+
+def isPalindrome(s, i):
+    if(i > len(s)/2):  #base case
+       return True
+    ans = False
+    if((s[i] is s[len(s) - i - 1]) and isPalindrome(s, i + 1)): #recursive step
+      ans = True
+    return ans
+ 
+str = "racecar"
+if (isPalindrome(str, 0)):
+    print("Yes")
+else:
+    print("No")
+