PYTHON - String Concatenation

Python - String Concatenation

Concatenate Strings in Python

String concatenationin Python is the operation of joining two or more strings together. The result of this operation will be a new string that contains the original strings. The diagram below shows a general string concatenation operation −

In Python, there are numerous ways to concatenate strings. We are going to discuss the following −

Using ’+’ operator
Concatenating String with space
Using multiplication operator
Using ’+’ and ’*’ operators together

String Concatenation using ’+’ operator

The ”+” operator is well-known as an addition operator, returning the sum of two numbers. However, the ”+” symbol acts as stringconcatenation operatorinPython. It works with two string operands, and results in the concatenation of the two.

The characters of thestringon the right of plus symbol are appended to the string on its left. Result of concatenation is a new string.

Example

The following example shows string concatenation operation in Python using + operator.

PYTHON CODE

str1="Hello"
str2="World"
print ("String 1:",str1)
print ("String 2:",str2)
str3=str1+str2
print("String 3:",str3)

It will produce the followingoutput−

PYTHON CODE

String 1: Hello
String 2: World
String 3: HelloWorld

Concatenating String with space

To insert a whitespace between two strings, we can use a third empty string.

Example

In the below example, we are inserting space between two strings while concatenation.

PYTHON CODE

str1="Hello"
str2="World"
blank=" "
print ("String 1:",str1)
print ("String 2:",str2)
str3=str1+blank+str2
print("String 3:",str3)

It will produce the followingoutput−

PYTHON CODE

String 1: Hello
String 2: World
String 3: Hello World

String Concatenation By Multiplying

Another symbol *, which we normally use for multiplication of two numbers, can also be used with string operands. Here, * acts as a repetition operator in Python. One of the operands must be an integer, and the second a string. The integer operand specifies the number of copies of the string operand to be concatenated.

Example

In this example, the * operator concatenates multiple copies of the string.

PYTHON CODE

newString = "Hello" * 3
print(newString)

The above code will produce the followingoutput−

PYTHON CODE

HelloHelloHello

String Concatenation With ’+’ and ’*’ Operators

Both the repetition operator () and the concatenation operator (+), can be used in a single expression to concatenate strings. The "" operator has a higher precedence over the ”+” operator.

Example

In the below example, we are concatenating strings using the + and * operator together.

PYTHON CODE

str1="Hello"
str2="World"
print ("String 1:",str1)
print ("String 2:",str2)
str3=str1+str2*3
print("String 3:",str3)
str4=(str1+str2)*3
print ("String 4:", str4)

To formstr3string, Python concatenates 3 copies of World first, and then appends the result to Hello

PYTHON CODE

String 3: HelloWorldWorldWorld

In the second case, the strings str1 and str2 are inside parentheses, hence their concatenation takes place first. Its result is then replicated three times.

PYTHON CODE

String 4: HelloWorldHelloWorldHelloWorld

Apart from + and *, no other arithmetic operators can be used with string operands.