View difference between Paste ID: BUc0WB0s and XpLBPec3

 function solveClasses() {
 
     class Developer {
         constructor(firstName, lastName) {
             this.firstName = firstName;
             this.lastName = lastName;
             this.baseSalary = 1000;
             this.tasks = [];
             this.experience = 0;
         }
         addTask(id, taskName, priority) {
             if (priority == "high") {
                 this.tasks.unshift({ id, taskName, priority });
             } else {
                 this.tasks.push({ id, taskName, priority });
             }
             return `Task id ${id}, with ${priority} priority, has been added.`
         }
         doTask() {
             if (this.tasks.length > 0) {
                 return this.tasks.shift();
             } else {
                 return `${this.firstName}, you have finished all your tasks. You can rest now.`
             }
         }
         getSalary() {
             return `${this.firstName} ${this.lastName} has a salary of: ${this.baseSalary}`;
         }
         reviewTasks() {
             let res = [];
             res.push("Tasks, that need to be completed:")
             this.tasks.forEach(x => {
                 res.push(`${x.id}: ${x.taskName} - ${x.priority}`);
             })
             return res.join('\n');
         }
     }
     class Junior extends Developer {
         constructor(firstName, lastName, bonus, experience) {
             super(firstName, lastName);
             this.experience = experience;
             this.baseSalary = 1000 + bonus;
         }
         learn(years) {
             this.experience += years;
         }
     }
     class Senior extends Developer {
         constructor(firstName, lastName, bonus, experience) {
             super(firstName, lastName);
             this.experience = experience + 5;
             this.baseSalary = 1000 + bonus;
         }
         changeTaskPriority(taskId) {
             let taskIndex = this.tasks.findIndex(x => x.id == taskId);
             let currTask = this.tasks[taskIndex];
             this.tasks = this.tasks.splice(taskIndex, 1);
             if (currTask.priority == 'low') {
                 currTask.priority = 'high'
                 this.tasks.unshift(currTask);
             } else {
                 currTask.priority = 'low';
                 this.tasks.push(currTask);
             }
             return currTask;
         }
 
     }
     return {
         Developer,
         Junior,
         Senior
     }
 }