How to learn game development?(PC and Mobile) [on hold]

I am an electronic undergraduate and none of my friends even in CS have idea how to become an independent game Dev or even work as a product engg./game Dev in a mobile based gaming startup.Sure they know full stack mobile app development is one part(on mobile),also working on some engine like Unity etc, but nothing more.Any idea what things are important and also some advice to non CS background guys on how to start?

Create an application that can help students in grade 1 through 3 learn how to make change

i would like anyone to help me on the following question. please you can inbox me via my email bmudzingwa8@gmail.com

Create an application that can help students in grade 1 through 3 learn how to make change. The application will allow the students to enter the amount of money a customer owes and the amount of money the customer paid. It then will calculate the amount of change, as well as the number of dollars, quarter, dimes, nickels and pennies to return to the customers. For now, you will not worry about the situation where the amount owed is greater than the amount paid. You will assume that the customer pays either the exact amount or more than then exact amount. For example your change should display how many N$ 200, N$ 100, N$ 50, N$ 20, N$ 10, N$ 5,50cents, 10cents and 5cents are returned to the customers.coding im using visual basic.

thanking you in anticipation.

How to make a line in d3js (Trying to learn d3js)

I am trying to implement a paint like feature using d3js as a learning project. My idea is that when the mouse is clicked it starts making a line wherever the mouse goes just like MS Paint. I initially tried to do it with just small circles but if I move the mouse quickly it is leaving a few blank spaces and I figured out that it must be due to amount of time an onclick event could be called. So decided to store all the coordinates in an array and than later loop through them and compare each coordinate with the next one and if both have the same x coordinates then make a verticle line bw the two coordinates and if both have the same y coordinates then make a horizontal line. But somehow my code is only working for the circle. Would really appreciate if someone helps me out

const svg = d3.select("#svg");     let drawing = false;     //to store coordinates for each time mouse moves      let data =[];      function drawPoint()     {         if(!drawing)             return;         const cords = d3.mouse(this);         console.log("The coords are" + cords)         data.push(cords);         console.log(data);          //loop through the coordinates          for(let i = 0; i < data.length - 1; i++)         {             console.log("inside loop");             console.log(data[i]);             if(data[i][0] === data[i+ 1][0])             {                 console.log("inside condition");                 //means a vertical line is been made                 svg.append("line")                     .attr("x1", data[i][0])     // x position of the first end of the line                     .attr("y1", data[i][1])      // y position of the first end of the line                     .attr("x2", data[i + 1][0])     // x position of the second end of the line                     .attr("y2", data[i +1][1])      // y position of the second end of the line                     .style("black", "stroke");             }             else if(data[i][1] === data[i+ 1][1])             {                 svg.append("line")                     .attr("x1", data[i][0])     // x position of the first end of the line                     .attr("y1", data[i][1])      // y position of the first end of the line                     .attr("x2", data[i + 1][0])     // x position of the second end of the line                     .attr("y2", data[i +1][1])      // y position of the second end of the line                     .style("black", "stroke");             }             else             {                 svg.append("circle")                     .attr("cx", data[i][0])                     .attr("cy", data[i][1])                     .attr("r", 5)                     .style("fill", "black");             }          }       }      svg.on("mousemove", drawPoint);         svg.on("mousedown", () => {         drawing = true;     });      svg.on("mouseup", () => {         drawing = false;     }); 

If I’m trying to learn how to write emulators, and I’ve already completed a CHIP-8 emulator, what should I try next? [on hold]

I’m trying to get comfortable writing emulators to get ready for a slightly ambitious and difficult emulation project which will be completed by me and two of my close friends. I’ve already completed a working CHIP-8 emulator in Java, for which I can link the source code if needed. I was advised by various StackExchange forums and a couple Reddit threads that if you want to get started with writing emulators, CHIP-8 was the way to go for a first project. I did so with the help of this very helpful tutorial and the CHIP-8 Wikipedia article. I really feel like I’ve learned a lot of new things from this and have expanded my knowledge on things I thought I’d had a pretty good grasp on. I’m wondering where I should go from here, as in what computer system I should attempt to emulate next when my only experience is in a CHIP-8 emulator. I do feel like I should try to tackle something a bit more challenging, but I don’t want to dive too deep and write a Nintendo Switch emulator or something like that.

Any thoughts or suggestions would be greatly appreciated.

What are some books to learn concept like preconditions and inductive invariants?

I may already have some knowledge about precondition and inductive invariant, but I would like if you could suggest for me some books from where I can learn in deep fondamental concepts like precondition, weakest precondition, invariant…?

I need to understand in deep those concept mainly in the world of formal methods and program verification.