LESSON 375 OF 410 · PROJECTS: COMMAND-LINE TOOLS

CLI Tool: head v3 — Cap n at lines.size() in Java

Practice

Same signature as v2, but now n may be larger than the number of lines. If n > lines.size() simply return all the lines (don't crash, don't pad). For this version assume n ≥ 0. If n is 0, or there are no lines, the result is the empty string.

Function signature:

public String head(List<String> lines, int n)

Example:

Input: lines = ["alpha", "beta", "gamma"], n = 10

Output: "alpha\nbeta\ngamma"

When printed:
alpha
beta
gamma

List.subList(0, n) with n > lines.size() throws. So clamp n with Math.min(n, lines.size()) first.

int end = Math.min(n, lines.size());
return String.join("\n", lines.subList(0, end));

The full solution:

class Solution {
    public String head(List<String> lines, int n) {
        int end = Math.min(n, lines.size());
        return String.join("\n", lines.subList(0, end));
    }
}

STEP 1 OF 2

Guided

Ctrl + Enter to check

CLI Tool: head v3 — Cap n at lines.size() in Java

Head V3 in Java