How to use the map function in this?

Tell us what’s happening:
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if let a = [45,20,64,87,96,54];

/* suppose I want to add a[i] + a[i+1] = b[i] which

  • is equal to (example “i=0”) a[0] + a[1] = b[0];
    *how to do that with the function map instead of a for loop?
    *because in the function map I don’t have a “i” variable.

const b = a.map(function(a) {
return
});

console.log(b);





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because in the function map I don’t have a “i” variable.

The map method does have an optional index variable and that’s the index of the current element being processed in the array.

To know more, you can have a look here: Array.prototype.map() - JavaScript | MDN

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It also passes in a reference to the array itself as a third parameter, so you don’t have to refer to an out of scope reference.

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