Python solution for day 10 and day 11 (#114)

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* Python solution for day 11

* Python solution for day10 and day11

Author: vishalshirke7

day10/Python/permutations1.py

@@ -0,0 +1,10 @@
+from itertools import permutations
+"""
+  @author : vishalshirke7
+  @date : 02/01/2019
+"""
+
+ip_str = input()
+perm = permutations(list(ip_str), len(ip_str))
+for i in set(list(perm)):
+    print("".join(map(str, i)))

day10/README.md

@@ -120,7 +120,7 @@ permut('123');
 
 ## Python Implementation
 
-### [Solution](./Python/permutations.py)
+### [Solution1](./Python/permutations.py)
 ```python
 
 '''
@@ -154,8 +154,28 @@ def main():
 main()
 ```
 
-### [Solution2](./Python/st_permutations.py)
+### [Solution 2 by @vishalshirke7](./Python/permutations1.py)
 ```python
+
+from itertools import permutations
+"""
+  @author : vishalshirke7
+  @date : 02/01/2019
+  
+  This solution makes use of python's in-build permutations function from itertools module
+  It takes two arguments 1st is the list on which permutation is to be performed and 
+  2nd is the length of the permutation
+"""
+
+ip_str = input()
+perm = permutations(list(ip_str), len(ip_str))
+for i in set(list(perm)):
+    print("".join(map(str, i)))
+```
+
+### [Solution 3 by @ashwek](./Python/st_permutations.py)
+
+```py
 """
   * @author: ashwek
   * @date 2/1/2019

day11/Python/lcs.py

@@ -0,0 +1,51 @@
+"""
+  @author : vishalshirke7
+  @date : 03/01/2019
+"""
+
+
+def lcs(str1, str2):
+    m, n = len(str1), len(str2)
+
+    L = [[0 for y in range(n + 1)] for x in range(m + 1)]
+
+    for i in range(m + 1):
+        for j in range(n + 1):
+            if i == 0 or j == 0:
+                L[i][j] = 0
+            elif str1[i - 1] == str2[j - 1]:
+                L[i][j] = L[i - 1][j - 1] + 1
+            else:
+                L[i][j] = max(L[i - 1][j], L[i][j - 1])
+
+    index = L[m][n]
+
+    # Create a character array to store the lcs string
+    lcs_str = [""] * (index + 1)
+    lcs_str[index] = ""
+
+    i = m
+    j = n
+    while i > 0 and j > 0:
+
+        # If current character in X[] and Y are same, then
+        # current character is part of LCS
+        if str1[i - 1] == str2[j - 1]:
+            lcs_str[index - 1] = str1[i - 1]
+            i -= 1
+            j -= 1
+            index -= 1
+
+        # If not same, then find the larger of two and
+        # go in the direction of larger value
+        elif L[i - 1][j] > L[i][j - 1]:
+            i -= 1
+        else:
+            j -= 1
+
+    print("LCS of " + str1 + " and " + str2 + " is -" + "".join(lcs_str))
+
+
+lcs(*(input().split()))
+
+

day11/README.md

@@ -192,3 +192,61 @@ public class longestCommonSubstring {
     }
 }
 ```
+
+## Python Implementation
+
+### [Solution using dynamic programming](./Python/lcs.py)
+
+```python
+"""
+  @author : vishalshirke7
+  @date : 03/01/2019
+"""
+
+
+def lcs(str1, str2):
+    m, n = len(str1), len(str2)
+
+    L = [[0 for y in range(n + 1)] for x in range(m + 1)]
+
+    for i in range(m + 1):
+        for j in range(n + 1):
+            if i == 0 or j == 0:
+                L[i][j] = 0
+            elif str1[i - 1] == str2[j - 1]:
+                L[i][j] = L[i - 1][j - 1] + 1
+            else:
+                L[i][j] = max(L[i - 1][j], L[i][j - 1])
+
+    index = L[m][n]
+
+    # Create a character array to store the lcs string
+    lcs_str = [""] * (index + 1)
+    lcs_str[index] = ""
+
+    # Start from the right-most-bottom-most corner and
+    # one by one store characters in lcs[]
+    i = m
+    j = n
+    while i > 0 and j > 0:
+
+        # If current character in X[] and Y are same, then
+        # current character is part of LCS
+        if str1[i - 1] == str2[j - 1]:
+            lcs_str[index - 1] = str1[i - 1]
+            i -= 1
+            j -= 1
+            index -= 1
+
+        # If not same, then find the larger of two and
+        # go in the direction of larger value
+        elif L[i - 1][j] > L[i][j - 1]:
+            i -= 1
+        else:
+            j -= 1
+
+    print("LCS of " + str1 + " and " + str2 + " is -" + "".join(lcs_str))
+
+
+lcs(*(input().split()))
+```