7️⃣

5.7 Nested Loops

5.7 Nested Loops

A nested loop where a loop is placed inside of another loop. The "inner loop" will be executed for very single iteration of the "outer loop".

Common Example

let activities = [
    ['Work', 9],
    ['Eat', 1],
    ['Commute', 2],
    ['Play Game', 1],
    ['Sleep', 7]
];
for (let i = 0; i < 5; i++) {
    for (let j = 0; j < 5; j++) {
        console.log(activities[i][j]);
    }
}

/* Output:
Work
9
Eat 
1
Commute
2
Play Game
1
Sleep
7
*/

Here the nested loop iterates through all the values in the 2D array. Then all the values are printed out to the console.

It is typical to use a nested loop to iterate through a 2D array.

Practice

You can add practice problems here if you want. Follow the format below.

Previous Section

6️⃣
5.6 2D Arrays

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