typescript

 export{}

function f1(a,...b){

let sum=0;

let c;

    // console.log(a);

    // console.log(b);

    // console.log(b.length);

    b.forEach(element => {

   sum=element+sum;     

    });

    sum=sum+a;

    console.log(sum);

    

}

f1(3,5,6,7,8,9,10);

//function f1(a:number,...b:number[])

export{}

function f1(a:number,b?:number){

let sum=0;

sum=b?a+b:a;

    console.log(sum);

    

}

f1(3);

export{}

class A{

    name;

    constructor(name){

this.name=name;

    }

     getdata(){

return this.name;

    }

}

let obj=new A("gaurav");

console.log(obj.getdata());

export{}

class A{

    name:string;

    constructor(name){

this.name=name;

    }

     getdata():string{

return this.name;

    }

}

class B extends A{

constructor(name){

    super(name);

    this.name="raj";

}

}

let obj=new B("gaurav");

console.log(obj.getdata());

export{}

interface datatype{

    name:string,

    lastname:string,

    getdata:()=>string,

}

const user:datatype={

    name:"gaurav",

    lastname:"pandey",

    getdata:function(){

      return  this.name+""+this.lastname;

    }

}