TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’

The TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’ emerges when attempting to add an integer value to a string that may potentially represent a valid integer. Python lacks automatic type casting in such scenarios. While you can perform addition operations between two integers or concatenate two strings, adding an integer to a string is not permissible in Python. The error, TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’, will be raised if an attempt is made to add an integer value to a Python string. To avoid this error, ensure consistent data types in your operations, either by converting the integer to a string or vice versa before the addition operation.

In Python, the plus symbol “+” serves a dual purpose—it can be used for both arithmetic addition of numbers and concatenation of strings. Arithmetic addition involves adding two numbers, while string concatenation combines two strings. However, attempting to concatenate a number and a string using the “+” operator is not supported in Python, leading to the error TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’.

Objects other than numbers cannot be subjected to arithmetic operations like addition or subtraction. If there is an attempt to add a number to a string that potentially contains a numeric value, the TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’ error will be raised. To resolve this, it is essential to convert the string to an integer before performing the addition operation with another numeric value. This ensures compatibility and prevents the occurrence of the mentioned error.

Exception

In this article, we explore the meaning and resolution of the TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’ error in Python. This error signifies a mismatch in concatenating two variables of different data types. The issue arises when attempting to combine an integer and a string using the “+” operator. The error message appears as follows:

Traceback (most recent call last):
  File "/Users/python/Desktop/test.py", line 3, in <module>
    print x + y
TypeError: unsupported operand type(s) for +: 'int' and 'str'
[Finished in 0.1s with exit code 1]

Understanding the nature of this error and implementing appropriate solutions is crucial for preventing and addressing such type mismatches in Python programming.

How to reproduce this issue

The following code snippet illustrates the concatenation of two separate data type values, an integer (x) and a string (y), using the plus “+” operator. This results in the TypeError: unsupported operand type(s) for +: ‘int’ and ‘str’ due to the mismatch between the data types:

x = 5
y = "Yawin Tutor"
print x + y

Output

Traceback (most recent call last):
  File "/Users/python/Desktop/test.py", line 3, in <module>
    print x + y
TypeError: unsupported operand type(s) for +: 'int' and 'str'
[Finished in 0.1s with exit code 1]

When you run this code snippet, you will encounter the mentioned TypeError, indicating an unsupported operand type for the addition operation between an integer and a string. To resolve this, you may need to convert the integer to a string or the string to an integer based on your intended operation.

Different Variation of the error

TypeError: unsupported operand type(s) for +: 'int' and 'str'
TypeError: unsupported operand type(s) for -: 'int' and 'str'
TypeError: unsupported operand type(s) for /: 'int' and 'str'
TypeError: unsupported operand type(s) for %: 'int' and 'str'
TypeError: unsupported operand type(s) for //: 'int' and 'str'
TypeError: unsupported operand type(s) for ** or pow(): 'int' and 'str'
TypeError: unsupported operand type(s) for +=: 'int' and 'str'
TypeError: unsupported operand type(s) for -=: 'int' and 'str'
TypeError: unsupported operand type(s) for /=: 'int' and 'str'
TypeError: unsupported operand type(s) for %=: 'int' and 'str'
TypeError: unsupported operand type(s) for //=: 'int' and 'str'
TypeError: unsupported operand type(s) for ** or pow(): 'int' and 'str'
TypeError: unsupported operand type(s) for &=: 'int' and 'str'
TypeError: unsupported operand type(s) for |=: 'int' and 'str'
TypeError: unsupported operand type(s) for ^=: 'int' and 'str'
TypeError: unsupported operand type(s) for <<=: 'int' and 'str'
TypeError: unsupported operand type(s) for >>=: 'int' and 'str'

Root Cause

The error occurs due to a mismatch of data types. Operators in Python are designed to operate on operands of the same data type. When an operator is applied to two different data types, a type mismatch error is triggered.

In a program, if the plus “+” operator is used with two separate data types, such as an integer and a string, it is necessary to convert them to the same data type before performing the operation. This ensures compatibility and prevents the type mismatch error from being raised.

Solution 1

Python does not support direct addition between a number and a string. To resolve the “TypeError: unsupported operand type(s) for +: ‘int’ and ‘str'” error, you need to ensure that both operands are of the same data type.

If you want to perform mathematical addition, you should convert the string to a number (int or float). Conversely, if you want to concatenate the values as strings, convert the number to a string.

Here’s an example illustrating both scenario:

# Example 1: Mathematical Addition
x = 5
y = "10"

# Convert the string to an integer before addition
result = x + int(y)
print(result)  # Output: 15

# Example 2: String Concatenation
a = 15
b = "20"

# Convert the number to a string before concatenation
concatenated_result = str(a) + b
print(concatenated_result)  # Output: "1520"

In Example 1, we convert the string y to an integer before adding it to the integer x. In Example 2, we convert the number a to a string before concatenating it with the string b. This ensures compatibility and resolves the type mismatch error.

Solution 2

If you’re referring to the second example provided earlier, where we demonstrated string concatenation, here’s a brief explanation:

# Example 2: String Concatenation
a = 15
b = "20"

# Convert the number to a string before concatenation
concatenated_result = str(a) + b
print(concatenated_result)  # Output: "1520"

In this example, the variable a is explicitly converted to a string using the str() function. Then, the + operator is used to concatenate the two variables (a and b). The result is a string where the values of a and b are joined together.

The output, as indicated in the comment, is "1520". This showcases the successful concatenation of two variables after ensuring they are of the same data type (both converted to strings).

Solution 3

The given program attempts to perform an addition operation between a string and an integer in Python. However, as Python does not permit the direct addition of different data types, it is necessary to convert both variables to the same data type. To facilitate this conversion, the Python str() function is employed, enabling the transformation of an integer to a string. Utilizing the str() function ensures uniform data types, allowing for the successful execution of the program without triggering a type mismatch error.

x = 5
y = "Yawin Tutor"
print str(x) + y

Output

5Yawin Tutor
[Finished in 0.1s]

Solution 4

When incorporating two variables into a print statement in Python, the print statement supports the inclusion of multiple parameters. This involves setting the string statement and the integer as two distinct parameters within the print statement. Notably, the print statement internally performs a conversion, ensuring that all values are represented as string statements in the output. The provided code exemplifies the usage of the print statement for this purpose.

x = 5
y = "Yawin Tutor"
print x , y

Output

5Yawin Tutor
[Finished in 0.1s]

Solution 5

In Python programming, dynamic string creation is facilitated by employing placeholders. By constructing a string that includes a designated placeholder, the Python program enables the dynamic insertion of values during runtime. Subsequently, at runtime, Python seamlessly substitutes the placeholder with the corresponding actual value, allowing for flexible and dynamic string generation.

x = 5
y = "Yawin Tutor"
print "{}".format(x) + y

or

print "{} Yawin Tutor".format(x)

Output

5 Yawin Tutor
[Finished in 0.1s]