class Vacation{
    constructor(organizer, destination, budget){
        this.organizer= organizer;
        this.destination=destination;
        this.budget= budget;
        this.kids={};
    }

    registerChild(name, grade, budget){
        if(!this.kids[grade]){

            this.kids[grade]=[];
        }

        if(budget<this.budget){
            return `${name}'s money is not enough to go on vacation to ${this.destination}.`
        }

        let exists=false;
        this.kids[grade].forEach(element => {
            let currName = element.split('-')[0];
            if (currName === name) {
                exists=true;
            }
        });

        if(exists){
            return `${name} is already in the list for this ${this.destination} vacation.`

        }

        this.kids[grade].push(`${name}-${budget}`);

        return this.kids[grade];
    }

    removeChild(name,grade){
        let foundKid=this.kids[grade].find(curr=>curr.split('-')[0]===name);
        if(foundKid){
            let ind=this.kids[grade].indexOf(foundKid);
            this.kids[grade].splice(ind,1);
            return this.kids[grade];
        }
        else{
            return `We couldn't find ${name} in ${grade} grade.`;
        }
    }

    toString(){
        Object.entries(this.kids).sort((a,b)=>{
            a[0]-b[0];
        })
        let result='';
        let num=0;
        Object.values(this.kids).forEach(arr=>{
            arr.forEach(kid=>num++);
        });

        result+= `${this.organizer} will take ${num} children on trip to ${this.destination}`

        Object.entries(this.kids).forEach(gradeKVP=>{
            let seq=0;
            if(gradeKVP[1].length>0){
                result+= `\nGrade: ${gradeKVP[0]}`;
                gradeKVP[1].forEach(kidLine=>{
                    let ind= gradeKVP[1].indexOf(kidLine);
                    result+= `\n${++seq}. ${kidLine}`;
                    // if(ind<gradeKVP[1].length-1){

                    // }
                    // else{
                    //     result+= `${++seq}. ${kidLine}`;
                    // }
                })
                result+= '\n';
            }
        })
        return `${result}`;
    }
}

let vacation = new Vacation('Miss Elizabeth', 'Dubai', 2000);
vacation.registerChild('Gosho', 5, 3000);
vacation.registerChild('Lilly', 6, 1500);
vacation.registerChild('Pesho', 7, 4000);
vacation.registerChild('Tanya', 5, 5000);
vacation.registerChild('Mitko', 10, 5500)
console.log(vacation.toString());