append array to array javascript

Question

i have an empty array and need to append array through a nested for loop.

const arr1=[ [ 1,3 ], [ 5,4 ], [ 8,6, 11 ], [ 15, 19, 12 ] ];
const arr2=[ [21,23],[ 3, 2 ], [ 1,4 ], [ 5, 6 ,11 ] ];
const arr3=[];
console.log('Lost assests counts');
for (let i=0;i<arr1.length;++i)
{
 const arrTemp=[]
 arrTemp.push(arr1[i].length)
 
 for (let j=i+1;j<arr2.length;++j){
 
 const intersection = arr2[j].filter(element => arr1[i].includes(element));
 arrTemp.push(intersection.length)
 
 
 }
 console.log(arrTemp);
}

This returns the below output(this is the output of arrTemp inside the loop):

enter image description here

Instead of the above output, Can I have it like the below way?

[[2,1,1,0],[2,1,1],[3,2],[3]]

• James: Printing? You should convert the array to a string to control what it looks like as output.
• zer00ne: define arrTemp outside of loops as let arrTemp = [] then put console.log(JSON.stringify(arrTemp)); outside of loops as well.

Answer 1

Did you just want to push the values to arr3? In that case, instead of printing the value within the loop:

console.log(arrTemp);

Push it to the target array in the loop:

arr3.push(arrTemp);

Then after the loop, print the whole thing:

console.log(arr3);

---

Full example:

const arr1=[ [ 1,3 ], [ 5,4 ], [ 8,6, 11 ], [ 15, 19, 12 ] ];
const arr2=[ [21,23],[ 3, 2 ], [ 1,4 ], [ 5, 6 ,11 ] ];
const arr3=[];
console.log('Lost assests counts');
for (let i=0;i<arr1.length;++i)
{
 const arrTemp=[]
 arrTemp.push(arr1[i].length)
 
 for (let j=i+1;j<arr2.length;++j){
 
 const intersection = arr2[j].filter(element => arr1[i].includes(element));
 arrTemp.push(intersection.length)
 
 
 }
 arr3.push(arrTemp); // I changed this
}
console.log(arr3); // I added this