Python: TypeError: cannot concatenate 'str' and 'int' objects

There are two ways to fix the problem which is caused by the last print statement.

You can assign the result of the str(c) call to c as correctly shown by @jamylak and then concatenate all of the strings, or you can replace the last print simply with this:

print "a + b as integers: ", c  # note the comma here

in which case

str(c)

isn't necessary and can be deleted.

Output of sample run:

Enter a: 3
Enter b: 7
a + b as strings:  37
a + b as integers:  10

with:

a = raw_input("Enter a: ")
b = raw_input("Enter b: ")
print "a + b as strings: " + a + b  # + everywhere is ok since all are strings
a = int(a)
b = int(b)
c = a + b
print "a + b as integers: ", c

str(c) returns a new string representation of c, and does not mutate c itself.

c = str(c) 

is probably what you are looking for

If you want to concatenate int or floats to a string you must use this:

i = 123
a = "foobar"
s = a + str(i)