diff --git a/baishali_issue_19.py b/baishali_issue_19.py
new file mode 100644
index 0000000..2bbec93
--- /dev/null
+++ b/baishali_issue_19.py
@@ -0,0 +1,6 @@
+# program to check leap year
+year = int(input("Enter a year: ")) 
+if (year % 4 == 0 and year % 100 != 0) or (year % 400 == 0):
+    print(f"{year} is a leap year.")
+else:
+    print(f"{year} is not a leap year.")
diff --git a/baishali_issue_21.py b/baishali_issue_21.py
new file mode 100644
index 0000000..3ca46cb
--- /dev/null
+++ b/baishali_issue_21.py
@@ -0,0 +1,13 @@
+# temperature converter issue 21
+unit=input("Is this temperature in Celsius or Fahrenheit? (C/F): ")
+temp= float(input("Enter the temperature you want to convert: "))
+if unit=="C":
+    converted_temp= (temp * 9/5) + 32
+    print(f"{temp} degree Celsius is equal to {converted_temp} degree Fahrenheit.")
+
+elif unit=="F":
+    converted_temp= (temp - 32) * 5/9
+    print(f"{temp} degree Fahrenheit is equal to {converted_temp} degree Celsius.")
+else:
+    print("Invalid unit. Please enter 'C' for Celsius or 'F' for Fahrenheit.")
+    
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diff --git a/baishali_issue_6.css b/baishali_issue_6.css
new file mode 100644
index 0000000..e69de29
diff --git a/baishali_issue_6.html b/baishali_issue_6.html
new file mode 100644
index 0000000..e69de29
diff --git a/baishali_issue_9.py b/baishali_issue_9.py
new file mode 100644
index 0000000..93c366e
--- /dev/null
+++ b/baishali_issue_9.py
@@ -0,0 +1,23 @@
+# program to swap two numbers
+#using temporary variable
+a=int(input("Enter first number: "))
+b=int(input("Enter second number: "))
+print(f"Before swapping: a ={a}, b ={b}")
+temp=a
+a=b 
+b=temp
+print(f"After swapping: a ={a}, b ={b}")
+#without using temporary variable
+a=int(input("Enter first number: "))
+b=int(input("Enter second number: "))
+print(f"Before swapping: a ={a}, b ={b}")
+a=a+b
+b=a-b
+a=a-b
+print(f"After swapping: a ={a}, b ={b}")
+#using python's special feature
+a=int(input("Enter first number: "))
+b=int(input("Enter second number: "))
+print(f"Before swapping: a ={a}, b ={b}")
+a,b=b,a
+print(f"After swapping: a ={a}, b ={b}")
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