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Indexing a String | Text Data Type
C++ Data Types
course content

Зміст курсу

C++ Data Types

C++ Data Types

1. Introduction
2. Numerical Data Types
3. Text Data Type
4. Other Data Types and Concepts

Indexing a String

We can access the elements of a string (which are chars) using indexing with square brackets [] just like we would do with an array. Using that, we can also replace a character at a given position.

With that indexing, you can try to access a wrong index (that is out of range), and the compiler will tell you nothing about that.

cpp

main

As you can see, the output is weird, and C++ did not warn you about the problem (as always...). To avoid it, you can get the length of a string using the .length() method and ensure your index is smaller than the length of your string.

cpp

main

Another way of indexing is using the .at() method. To get the character with index n, we can use the following syntax:

It works the same as str[n] but will raise an error if you specify an index that is out of range.

cpp

main

Try outputting the character with the index 5 in the code window above.

Let's sum up what we used in this chapter:

Practice

As was said before, we can replace the characters inside a string using indexing (both with [] and .at()). Here is an example:

cpp

main

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Все було зрозуміло?

Секція 3. Розділ 3
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Indexing a String

We can access the elements of a string (which are chars) using indexing with square brackets [] just like we would do with an array. Using that, we can also replace a character at a given position.

With that indexing, you can try to access a wrong index (that is out of range), and the compiler will tell you nothing about that.

cpp

main

As you can see, the output is weird, and C++ did not warn you about the problem (as always...). To avoid it, you can get the length of a string using the .length() method and ensure your index is smaller than the length of your string.

cpp

main

Another way of indexing is using the .at() method. To get the character with index n, we can use the following syntax:

It works the same as str[n] but will raise an error if you specify an index that is out of range.

cpp

main

Try outputting the character with the index 5 in the code window above.

Let's sum up what we used in this chapter:

Practice

As was said before, we can replace the characters inside a string using indexing (both with [] and .at()). Here is an example:

cpp

main

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Все було зрозуміло?

Секція 3. Розділ 3
toggle bottom row

Indexing a String

We can access the elements of a string (which are chars) using indexing with square brackets [] just like we would do with an array. Using that, we can also replace a character at a given position.

With that indexing, you can try to access a wrong index (that is out of range), and the compiler will tell you nothing about that.

cpp

main

As you can see, the output is weird, and C++ did not warn you about the problem (as always...). To avoid it, you can get the length of a string using the .length() method and ensure your index is smaller than the length of your string.

cpp

main

Another way of indexing is using the .at() method. To get the character with index n, we can use the following syntax:

It works the same as str[n] but will raise an error if you specify an index that is out of range.

cpp

main

Try outputting the character with the index 5 in the code window above.

Let's sum up what we used in this chapter:

Practice

As was said before, we can replace the characters inside a string using indexing (both with [] and .at()). Here is an example:

cpp

main

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Все було зрозуміло?

We can access the elements of a string (which are chars) using indexing with square brackets [] just like we would do with an array. Using that, we can also replace a character at a given position.

With that indexing, you can try to access a wrong index (that is out of range), and the compiler will tell you nothing about that.

cpp

main

As you can see, the output is weird, and C++ did not warn you about the problem (as always...). To avoid it, you can get the length of a string using the .length() method and ensure your index is smaller than the length of your string.

cpp

main

Another way of indexing is using the .at() method. To get the character with index n, we can use the following syntax:

It works the same as str[n] but will raise an error if you specify an index that is out of range.

cpp

main

Try outputting the character with the index 5 in the code window above.

Let's sum up what we used in this chapter:

Practice

As was said before, we can replace the characters inside a string using indexing (both with [] and .at()). Here is an example:

cpp

main

Завдання

Your task is to check if we can add characters to the end of a string that way.

  • Figure the index of the last character in a string.
  • Assign 'y' to the index index of last character + 1 of str.

Секція 3. Розділ 3
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