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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice map()

Tadjiev Codes
Tadjiev Codes
9,626 Points
Posted by Tadjiev Codes
Tadjiev Codes
9,626 Points

Use the map method on the daysOfWeek array, creating a new array of abbreviated week days. Each abbreviated string shoul

Use the map method on the daysOfWeek array, creating a new array of abbreviated week days. Each abbreviated string should be the first three letters of the long version in daysOfWeek. Store the new array in the variable abbreviatedDays.

app.js 
const daysOfWeek = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
let abbreviatedDays;

// abbreviatedDays should be: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]
// Write your code below
 abbreviatedDays = daysOfWeek.map(days => days.charAt(0)  );

3 Answers

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

The "charAt" method will return just one single character. You could potentially call it 3 times and combine with concatenation.

For creating a 3-letter abbreviation more compactly you might find "slice" or "substring" useful.

Tadjiev Codes
Tadjiev Codes
9,626 Points
Tadjiev Codes
Tadjiev Codes
9,626 Points

Thanks and yes

abbreviatedDays = daysOfWeek.map(days => days.substr(0,3) );

This works So it starts from index 0 and goes until index 3? It stops after third letter so means normal 1 2 3 counting

Jacob TRAN
Jacob TRAN
653 Points
Jacob TRAN
Jacob TRAN
653 Points

I'd recommend look into slice as well