assignment.js

/* Q1. write a javascript program to find the area of a rectangle using a function. where users can enter the value run time and see the result in the browser */

//A1:-

//declare variables

/*
let width = 10; //prompt concept
let length;
//create a function
function Area(width = 4, length = 6){ //default assignment
  return (width * length);
}

//call
console.log("area of rectangle is" + " " + Area(width, length) );
*/

/* Q2. write a program to print the below pattern of stars.
*
**
***
****
***** */

//A2:-

/*
for (var i=1; i<=5; i++){
  console.log("*".repeat(i));
}
*/

//using repeat() method to construct and return specified copies, concatenated together.


//A2:-

/*
let i,j;
for(i=1; i<6; i++){
  for(j=1; j<=i; j++){
  }
  console.log("* ".repeat(i));
}
*/

/* Q3. write a program to print the pyramid of stars. */ 

//A3.


function pyramid(n){
  for(let i=1; i<=n; i++){
    let str =" ".repeat(n-i);
    let str2 ="*".repeat(i*2 -1)

    console.log(str + str2 + str);
  }
}
pyramid(5);



/* Q4. write a program named displayname() which will print your name. but this function will pass as a callback to another function named main() pass your name from main() and argument and print in the console via displayname(). */

//A4. 

/*
function main(firstname, lastname){
  console.log("hello, my name is " + firstname + " " + lastname); 
}
//callback function
function displayname(){
  main("vinay", "choudhary");
}
displayname();
*/


/* Q5. what is the output of below code and why? */

//A5.

/*
let obj1 = { name: "Monday" };
let obj2 = { name: "Monday" };
console.log(obj1 == obj2);
*/

//Output = False
//1. obj1 and obj2 are in global frame.

/* Q6. What is the output of below code and why? */

//A6.
/*
function display(MyName)
{
let userName = MyName || "CK";
console.log(userName);
return true
}
display('Yuvraj')
*/

//Output = yuvraj
//1. display() points console.log(username)(101)
//2. myname is assign to "yuvraj" and username is also "yuvraj"(97,98)

/* Q7. Explain the output of the below code. */

//A7.

/*
for (let i = 0; i < 5; i++) {
  if (i == 2) {
  continue;
  }
  console.log(i);
  for (let i = 0; i <= 3; i++) {
  if (i == 2) {
  break;
  }
  console.log(`i:${i}`);
  }
  }
*/

/*
Output = 0
         i:0
         i:1
         1
         i:0
         i:1
         3
         i:0
         i:1
         4
         i:0
         i:1  
*/

//1. it will print zero from the first for loop, console.log(i).
//2. it will print i:0, i:1 from the second for loop, console.log(`i:${i}`) and continue till if condition(i==2)(SECOND IF CONDITION) and breaks the loop and will move to the first loop again.
//3. same process for each until it reaches the (i==2)(FIRST IF CONDITION) condition and will CONTINUE THE LOOP AGAIN FROM START and after the execution of continue statement the loop will print same  for 3 and 4 and the execution will be terminated as i<5. 


/* Q8. - Explain the output of the below code. */

//A8. 

/*
let value = 0;
if (-2) {
var value = 10;
}
console.log(value);
*/

//Output = cannot execute(SyntaxError)
//1. Identifier 'value'(157) has already beed declared at(155).
//2. same identifier clash between global and block scope.

/* Q9. Explain the output of the below code. */

//A9.

/*
console.log(add);
var add = function (a, b) {
const results = a + b;
return results;
};
*/

//Output = Undefined
//1. at console.log add is undefined.


/* Q10.  Explain the result of the below codes? */

//A10. 

/*
let results = ((4 + 5) / 3) ** 2
console.log(results)
let result = NaN && null || '0' && 0
console.log(result)
*/

//console.log(0 === 0);

//Output = 9,0
//1. Operator Precedence...
//2. ** is is exponentiation
//3. the output 9 is from the first two lines(187,188) i.e (4+5) is 9 and 9/3 is 3 and 3**2 is 9. 
//4. compare all one by one(189) i.e NaN == NaN is false and NaN === NaN is false, null == null is true and null === null is true, '0' == '0' is true and '0' === '0' is true, 0 == 0 is true and 0 === 0 is true.
//5. the &&(AND) operator returns is left side value and the ||(OR) operator returns the right side value.