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Arrays, maps and ranges

An array is an ordered list, a map pairs keys with values, and a range counts from one number to another:

pleno

let colors = ["red", "magenta", "violet"];
colors.push("blue");
print(colors[0], colors.length);

let ages = {"Ada": 36, "Alan": 41};
ages["Grace"] = 85;
print(ages["Ada"], ages.keys());

print((1..=5).toArray());   // 1 to 5; 1..5 stops before 5

Run

for (item in collection) visits each element.

Your turn

Add up the scores in the map and print the total.

Arrays, maps and ranges ​

Your turn ​

Arrays, maps and ranges

Your turn