[Term Entry] C++ vector .back() (#5505)

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content/cpp/concepts/vectors/terms/back/back.md

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+---
+Title: '.back()'
+Description: 'Used to access the last element in a vector.'
+Subjects:
+  - 'Computer Science'
+  - 'Game Development'
+Tags:
+  - 'Vectors'
+  - 'Programming'
+  - 'Data Structures'
+  - 'Methods'
+CatalogContent:
+  - 'learn-c-plus-plus'
+  - 'paths/computer-science'
+---
+
+The C++ **`.back()`** method is used to access the last element in a vector. It views or modifies the element without removing it from the vector. This method is primarily used to access the most recently added element.
+
+## Syntax
+
+```pseudo
+vectorName.back();
+```
+
+## Example
+
+The below example shows the use of `.back()` method in c++ vectors, here `numbers` is a vector which has 5 elements in it and it displays the last element in the vector with the help of the `.back()` method, then the last element in the vector is modifies and the modified value is displayed.
+
+```cpp
+#include <iostream>
+#include<vector>
+//This is compulsory to include vectors while using vectors.
+
+int main(){
+  std::vector<int>numbers = {10,20,40,50,60};
+  std::cout<<"The last element in the vector is: "<< numbers.back()<< std::endl;
+  numbers.back() = 80;
+  std::cout <<"The last element in the vector after modification is: "<<numbers.back() <<std::endl;
+  return 0;
+  }
+```
+
+The output of the above code:
+
+```shell
+The last element in the vector is: 60
+The last element in the vector after modification is: 80
+```
+
+## Codebyte Example
+
+This codebyte example shows how a last element in the vector is accessed and modified using the `back()` method:
+
+```codebyte/cpp
+#include <iostream>
+#include <vector>
+int main() {
+  std::vector<int> numbers = {100, 90, 80, 70, 60};
+  std::cout << numbers.back() << std::endl;
+  numbers.back() = 10;
+  std::cout << numbers.back() << std::endl;
+  return 0;
+}
+```