Added Content in Pointers in Array: Fixed #269 (#287)

* Update pointers-in-array.md

Added reading content along with example programs

* Added Content in string-in-cpp.md

Added reading content, example programs, and a detailed list of string functions in cpp.

---------

Co-authored-by: Shubhadip Bhowmik <[email protected]>

docs/day-10/string-in-cpp.md

@@ -178,4 +178,4 @@ std::string myString(cStyleString);
 ```
 
 ### How to Split a String in C++?
-To split a string using a delimiter, we can use std::getline combined with std::stringstream to extract all the tokens from the string separated by a specified delimiter, and keep storing the token in a vector of string.
+To split a string using a delimiter, we can use std::getline combined with std::stringstream to extract all the tokens from the string separated by a specified delimiter, and keep storing the token in a vector of string.

docs/day-11/pointers-in-array.md

@@ -6,26 +6,77 @@ sidebar_label: "Pointers in Array"
 slug: pointers-in-array-in-cpp
 ---
 
-TASK:
+### 1. What are Pointers in Array?
+- In C++, pointers can be used with arrays to access their elements and perform operations. So, when we define a pointer to an array, we are essentially creating a pointer that points to the same address as the array name.
+- Here is a simple program that demonstrates the use of pointers in array.
+```cpp
+#include <iostream> 
+using namespace std; 
 
+int main() 
+{ 
+ int arr[5] = { 10, 20, 30, 40, 50 }; 
+ int* ptr = arr; //Pointer to the first element of an array
+
+ cout << "*arr = " << *arr << endl; //An array name is a pointer to its first element
+ cout << "arr = " << arr << endl; 
+ cout << "*ptr = " << *ptr << endl; 
+ cout << "ptr = " << ptr << endl; 
+
+ return 0; 
+}
+
+```
+Output
+```
+*arr = 10
+arr = 0x7ffc096e3bc0
+*ptr = 10
+ptr = 0x7ffc096e3bc0
+```
+
+### 2. Why do we need pointers in array?
+- They provide a way to pass arrays to functions without passing the entire array (which can be inefficient if the array is large).
+- They allow us to dynamically allocate memory for arrays at runtime.
+- They can be used to implement data structures like linked lists, trees, etc.
+
+### 3. Example Program to Traverse an Array using Pointer
+```cpp
+#include<iostream>
+using namespace std;
+
+int main() {
+ int arr[] = {18, 23, 36, 45, 57};
+ int *ptr = arr; // Pointer to the first element of the array
+
+ for(int i = 0; i < 5; i++) {
+  cout << "Element at index " << i << " is: " << *(ptr + i) << endl;
+ }
+
+ return 0;
+}
+```
+Output
+```
+Element at index 0 is: 18
+Element at index 1 is: 23
+Element at index 2 is: 36
+Element at index 3 is: 45
+Element at index 4 is: 57
+```
+Here,
+- arr is an Array of Integers.
+- *ptr is a Pointer that points to the first element of the Array arr.
+- The for loop iterates over each element of the array. *(ptr + i) gives the value at the ith index of the array. This is because adding i to the pointer ptr moves it i places in memory. Since ptr is a pointer to an integer, each move is the size of an integer.
+
+### Practice Questions
 1. What is a Pointer in C++?
 2. Explain the Syntax of a Pointer in C++.
 3. How to Declare and Define a Pointer in C++?
 4. How to Access the Value of a Pointer in C++?
 5. How to Access the Address of a Pointer in C++?
 6. How to Declare and Define a Pointer to a Pointer in C++?
-7. How do you initialize a pointer to point to the first element ofan array?
-8. Explain how pointer arithmetic works in the context of arrays?
-9. How can you pass an array to a function using pointers?
-10. What is the significance of null pointer in C++?
-11. How do you iterate over an array using pointers?
-12. Explain how memory is managed when using pointers with array in C++?
-13. What is a pointer decay and how does it related to array?
-14. Write a program to swap two elements in array using pointers?
-15. How do you dynamically allocate an array using pointers?
-
-
-Add more...
+
 
 IMAGE FILE:
 ![Function in CPP](../../static/img/day-11/array-with-pointers.png)