Build a tiny version of the Unix wc -w command. Given a list of lines, return the total number of words (whitespace-separated tokens) across all lines as an integer.
Function signature:
countWords(lines: string[]): number
Example:
Input: lines = ["hello world", "foo bar baz", ""] Output: 5
The empty string contributes 0 words, "hello world" contributes 2, and "foo bar baz" contributes 3. Total: 5.
Words are separated by one or more spaces or tabs, and leading or trailing whitespace is ignored. A line with no words (empty, or only whitespace) contributes 0, and an empty list of lines gives 0. The input is plain ASCII text.
Iterate over the lines, split on whitespace, and accumulate the count. Watch out for empty lines: they should contribute zero, not one.
Use
line.trim().split(/\s+/).filter(x => x).length. The filter drops the empty token that split produces for empty strings.
The full solution:
class Solution {
countWords(lines: string[]): number {
let total = 0;
for (const line of lines) {
const tokens: string[] = line.trim().split(/\s+/).filter(x => x);
total += tokens.length;
}
return total;
}
}
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