technical Blogs

today I will speak about one of the most important topics which are graph theory. I will take a long time in this series because I wanna speak a lot of data structure related to graph theory but in the beginning, I will speak about just two representations which are  (adjacency matrix, adjacency list). adjacency matrix the first let's talk about adjacency matrix .this to make a memory representation for any graph (directed or non-directed) we can imagine that Like  code bool adjacency_matrix[100][100];        Example n=3 0 1 0 1 1 0 0 1 1 for(int i=0;i<n;i++) for(int j=0;j<;j++){ int x; cin>>x; adjacency_matrix[i][j]=x; } adjacency list then I will speak about adjacency list, how to represent it in memory and how we implement it with code code vector< vector<int> > adjList1;               if adjacency list without  weight vector< vector< pair<int, int> ...

in this article, we will talk about Cumulative sum but first, let me talk about one of the most  a common problem in computer science if we have an array and we wanna calculate the summation  of a specific range in this array, you will think of nested loops that sound good.  but this solution is (o(n)^2) can we get a better solution ?? Yes, we can do that by using (cumulative sum). ok, what is that exactly? The cumulative sum is a technic we use to get the   summation of a specific range in an array in(o(i)). by generating a new array each element in that array contain the summation of elements before that  element. ok, How we can write this code? ZERO BASED int range(int s,int e,vector<int>&v){ if(s==0)     return v[e];     return v[e]-v[s-1]; } int main() { //zero based     vector<int>v={1,2,3,4,5,6};     vector<int>s(v.size(),0);     for(int i=0;i<v.size();i++)...

In this article I will speak about one of the main topics in computer science and I will write some examples to make you know what is that and how you should use it.   Recursion function it’s a function call itself. And this function is consisting of three parts (Base Case, some Logic,  Sub-problem). 1-Base case: this is a case when it happens this recursion function should stop and gave you the result.     2- some Logic: which happens when function called himself. 3- Sub-problem: in this part, the function calls itself by part of it but this calling should never go to infinity. Ex1: void SayHello(int num) {     if(num < 1)                                                     ...