The program takes a number and reverses it.

1prime.py

@@ -0,0 +1,22 @@
+# Python program to check if the input number is prime or not
+
+num = 407
+
+# take input from the user
+# num = int(input("Enter a number: "))
+
+# prime numbers are greater than 1
+if num > 1:
+   # check for factors
+   for i in range(2,num):
+       if (num % i) == 0:
+           print(num,"is not a prime number")
+           print(i,"times",num//i,"is",num)
+           break
+   else:
+       print(num,"is a prime number")
+
+# if input number is less than
+# or equal to 1, it is not prime
+else:
+   print(num,"is not a prime number")

Infix_and_Postfix.py

@@ -0,0 +1,58 @@
+#!/usr/bin/python
+#https://ragsagar.wordpress.com
+
+postfix = []
+temp = []
+operator = -10
+operand = -20
+leftparentheses = -30
+rightparentheses = -40
+empty = -50
+
+def precedence(s):
+    if s is '(':
+        return 0
+    elif s is '+' or '-':
+        return 1
+    elif s is '*' or '/' or '%':
+        return 2
+    else:
+        return 99
+
+def typeof(s):
+    if s is '(':
+        return leftparentheses
+    elif s is ')':
+        return rightparentheses
+    elif s is '+' or s is '-' or s is '*' or s is '%' or s is '/':
+        return operator
+    elif s is ' ':
+        return empty    
+    else :
+        return operand                          
+
+
+infix = raw_input("Enter the infix notation : ")
+for i in infix :
+    type = typeof(i)
+    if type is leftparentheses :
+        temp.append(i)
+    elif type is rightparentheses :
+        next = temp.pop()
+        while next is not '(':
+            postfix.append(next)
+            next = temp.pop()
+    elif type is operand:
+        postfix.append(i)
+    elif type is operator:
+        p = precedence(i)
+        while len(temp) is not 0 and p <= precedence(temp[-1]) :
+            postfix.append(temp.pop())
+        temp.append(i)
+    elif type is empty:
+        continue
+
+while len(temp) > 0 :
+    postfix.append(temp.pop())
+
+print "It's postfix notation is ",''.join(postfix)

prime.py

@@ -0,0 +1,22 @@
+# Python program to check if the input number is prime or not
+
+num = 407
+
+# take input from the user
+# num = int(input("Enter a number: "))
+
+# prime numbers are greater than 1
+if num > 1:
+   # check for factors
+   for i in range(2,num):
+       if (num % i) == 0:
+           print(num,"is not a prime number")
+           print(i,"times",num//i,"is",num)
+           break
+   else:
+       print(num,"is a prime number")
+
+# if input number is less than
+# or equal to 1, it is not prime
+else:
+   print(num,"is not a prime number")

reverse.py

@@ -0,0 +1,7 @@
+n=int(input("Enter number: "))
+rev=0
+while(n>0):
+    dig=n%10
+    rev=rev*10+dig
+    n=n//10
+print("Reverse of the number:",rev)