diff --git a/.idea/PythonAlgorithms.iml b/.idea/PythonAlgorithms.iml
new file mode 100644
index 0000000..7a98866
--- /dev/null
+++ b/.idea/PythonAlgorithms.iml
@@ -0,0 +1,13 @@
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\ No newline at end of file
diff --git a/.idea/libraries/R_User_Library.xml b/.idea/libraries/R_User_Library.xml
new file mode 100644
index 0000000..71f5ff7
--- /dev/null
+++ b/.idea/libraries/R_User_Library.xml
@@ -0,0 +1,6 @@
+<component name="libraryTable">
+  <library name="R User Library">
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+    <SOURCES />
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\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..a302abd
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,4 @@
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+<project version="4">
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\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 0000000..b663e83
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/PythonAlgorithms.iml" filepath="$PROJECT_DIR$/.idea/PythonAlgorithms.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..94a25f7
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
new file mode 100644
index 0000000..ee18953
--- /dev/null
+++ b/.idea/workspace.xml
@@ -0,0 +1,271 @@
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+      <provider selected="true" editor-type-id="text-editor" />
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+    </entry>
+    <entry file="file://$PROJECT_DIR$/LeetCode/0316_Remove_Duplicate_Letters.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="75">
+          <caret line="5" lean-forward="true" selection-start-line="5" selection-end-line="5" />
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\ No newline at end of file
diff --git a/LeetCode/0316_Remove_Duplicate_Letters.py b/LeetCode/0316_Remove_Duplicate_Letters.py
new file mode 100644
index 0000000..25c1347
--- /dev/null
+++ b/LeetCode/0316_Remove_Duplicate_Letters.py
@@ -0,0 +1,5 @@
+class Solution:
+    def removeDuplicateLetters(self, str):
+        s = set(str)
+        s = "".join(s)
+        print(s)
diff --git a/LeetCode/1661_Check_If_A_Number_is_Prime.py b/LeetCode/1661_Check_If_A_Number_is_Prime.py
new file mode 100644
index 0000000..78e3f9d
--- /dev/null
+++ b/LeetCode/1661_Check_If_A_Number_is_Prime.py
@@ -0,0 +1,8 @@
+class Solution:
+    def checkIfANumberIsPrime(self, num: int):
+           for i in range(2, num):
+                  if (num % i) == 0:
+                         print(num, "is not a prime number")
+                         break
+           else:
+                  print(num, "is a prime number")