Just practicing

practice.js

// function Employee(name, dept) {
//     this.name = name;
//     this.dept = dept;
// }

// Employee.prototype = {
//     getName() {
//         return this.name;
//     },
//     getDept() {
//         return this.dept
//     }
// };

// function Manager(name, dept) {
//     Employee.call(this, name, dept);
//     this.reports = []
// };

// Manager.prototype = Object.create(Employee.prototype);
// Manager.prototype.constructor = Manager;

// Manager.prototype.addReport = function(name, dept) {
//     const emp = new Employee(name, dept);
//     this.reports.push(emp);
// }

// Manager.prototype.getReports = function() {
//     return this.reports;    
// }

// function WorkerBee(name, dept) {
//     Employee.call(this, name, dept);
//     this.projects = []
// };

// WorkerBee.prototype = Object.create(Employee.prototype);
// WorkerBee.prototype.constructor = WorkerBee;

// WorkerBee.prototype.addProject = function(project) {
//     this.projects.push(project);
// }

// WorkerBee.prototype.getProjects = function() {
//     return this.projects;
// }

// function SalesPerson(name) {
//     WorkerBee.call(this, name, 'sales');
//     this.quota = 100;
// }

// SalesPerson.prototype = Object.create(WorkerBee.prototype);
// SalesPerson.prototype.constructor = SalesPerson;

// function Engineer(name) {
//     WorkerBee.call(this, name, 'engineering');
//     this.machine = "";
// }

// Engineer.prototype = Object.create(WorkerBee.prototype);
// Engineer.prototype.constructor = Engineer;

// Engineer.prototype.addMachine = function(machine) {
//     this.machine = machine;
// }

// Engineer.prototype.getMachine = function() {
//     return this.machine;
// }

// const chris = new Engineer('Chris Nolan');
// console.log(chris.getDept())
// chris.addMachine('Director');
// console.log(chris.getMachine());
// chris.addProject('Interstellar');
// console.log(chris.getProjects());

// function fibonacci(n) {
//     if(n === 0) return 0;
//     if(n === 1) return 1;

//     return fibonacci(n - 1) + fibonacci(n - 2);
// }



// console.log(fibonacci(12))

// function* fibonacciIt() {
//     let fn1 = 0;
//     let fn2 = 1;

//     while(true) {
//         let current = fn1;
//         fn1 = fn2;
//         fn2 = current + fn1;
//         let reset = yield current;
//         if(reset) {
//             fn1 = 0;
//             fn2 = 1;
//         }
//     }
// }

// let fib = fibonacciIt();
// console.log(fib.next().value);
// console.log(fib.next().value);
// console.log(fib.next().value);
// console.log(fib.next().value);
// console.log(fib.next().value);
// console.log(fib.next().value);
// console.log(fib.next(true).value);


const handler = {
    get(target, name) {    
        return target[name];
    },

    set(target, name, value) {
        target[name] = value;        
    }
}

const p = new Proxy({}, handler);
p.a = 1;
console.log(p.a)
p.b = 2;


console.log(p.b)


const nums = [3, 2, 1, 100, 4, 200];

nums.sort(function(num1, num2) {
    return num1 - num2;
});

console.log(nums)


function createChessBoard() {
    const size = 8;
    let board = "";

    for(let x = 0; x < size; x++) {
        for(let y = 0; y < size; y++) {
            if((x+y) % 2 === 0) {
                board += "#"
            } else {
                board += " "
            }
        }
        board+="\n"
    }
    console.log(board);
}

createChessBoard();


function first(word) {
    return word[0].toUpperCase();
}

const sentence = ["for", "your", "information"];
const acronym = sentence.map(first);
console.log(acronym.join(''));


Array.matrix = function(rows, cols, initial = 0) {
    let arr = [];
    for(let i = 0;i <rows; ++i) {
        let columns = [];

        for(let j=0; j<cols; ++j) {
            columns[j] = initial;
        }
        arr[i] = columns
    }

    return arr;
}

var matrix = Array.matrix(5, 5, 0);
console.log(matrix);


const grades = [[89, 77, 78],[76, 82, 81],[91, 94, 89]];

let total = 0;
let average = 0;

for(let row = 0; row < grades.length; ++row) {
    for(let col = 0; col < grades[row].length; ++col) {
        total += grades[row][col];
    }

    average = total / grades[row].length;
    console.log('Student ' + parseInt(row+1) + ' got an average : ' + average.toFixed(2));

    total = 0;
    average = 0;
} 


let somesentence = 'Gone with the wind';
let tempArr = somesentence.split(' ');
console.log('Backward ' + tempArr.reverse().join(' '));


function List() {
    this.listSize = 0;
    this.pos = 0;
    this.dataStore = [];
}

List.prototype = {
    append(element) {
        this.dataStore[this.listSize] = element;
        this.listSize++;
    },

    find(element) {
        for(let i=0; i<this.dataStore.length; i++) {
            if(this.dataStore[i] === element) {
                return i
            }
        }
        return -1;
    },

    remove(element) {
        const foundAt = this.find(element);

        if(foundAt > -1) {
            this.dataStore.splice(foundAt, 1);
            --this.listSize;
            return true;
        } else {            
            return false;
        }
    },
    length() {
        return this.listSize
    },

    toString() {
        return this.dataStore;
    },
    insert(element, after) {
        const insertPos = this.find(after);

        if(insertPos > -1) {
            this.dataStore.splice(insertPos + 1, 0, element);
            ++this.listSize;
            return true;
        } else {
            return false;
        }
    },

    clear() {
        delete this.dataStore;
        this.dataStore = [];
        this.listSize = 0;
    },

    contains(element) {
        for(let i=0; i<this.dataStore.length; i++) {
            if(this.dataStore[i] === element) {
                return true;
            }
        }
        return false;
    },

    front() {
        this.pos = 0
    },

    end() {
        this.pos = this.listSize - 1;
    },

    prev() {
        if(this.pos > 0) {
            --this.pos
        }
    },

    next() {
        if(this.pos < this.listSize - 1) {
            ++this.pos;
        }
    },

    currPos() {
        return this.pos;
    },

    moveTo(position) {
        this.pos = position;
    },

    getElement() {
        return this.dataStore[this.pos];
    }
}