Length starts from 0, yes?

#1


See, the output here is ‘‘e’’, but why? it says u have to count from 0, so in this case it should be ‘‘v’’…hm

The length of an empty string ("") is 0. Length is the number of characters in the string (or items in the array).

const str = 'abcde';

str[0]; // a
str[1]; // b
str[2]; // c
str[3]; // d
str[4]; // e

str.length; // 5

str[str.length - 1]; // e
str[str.length - 2]; // d
str[str.length - 3]; // c
str[str.length - 4]; // b
str[str.length - 5]; // a

The math all adds up.

See fencepost error for an explanation if you’re still confused. You can think of array/string indexes as fence panels and array/string lengths as the ending fence posts.

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