Data Structures and Algorithms

What is DSA ? : An efficient way to store and manipulate data

Why DSA ?

• Better problem solving
• Efficient memory management

Types of Data Structures

• Arrays
• Linked Lists
• Stacks
• Queues
• Trees
• Heaps

Arrays

• A contiguous memory stored Data structure.
• Memory is contiguous meaning there are elements in the consecutive memory space.

Insertion:

• They are done in the first and last position of the array.
• in cpp the arrays are dynamic by using 'vector'.

//assume an array named arr
vector<int> arr = {1,3,5,7,9}
arr.push_back(11); 
// this will insert 11 to the last position of the array
		

Deletion:

• To delete the last element in an dynamic array,

vector <int> arr = {1,2,3,4,5};
arr.pop_back();
// this will pop the last element out and only remaining elements exists in the array
		

Traversing:

• To traverse through an array, just use a for loop to get through every index of the array.

vector <int> arr = {1,2,3,4,5,6};
int n = arr.size();
for (int i = 0; i < n; i++){
	cout << arr << " "; 
		}
// this will loop through the array and prints the elements. 
		

Finding maximum element in an array

• Check if the array is sorted, if not sort it for better result
• If the array is sorted, then check whether the next element in an array is greater than the previous element

vector <int> arr = {1,2,3,4}
int n = arr.size();
int max = arr[0];

for(int i=1; i<n; i++){
	if(arr[i] > max) max = arr[i];
}
return max;