Starting with the n th element (with.Java)

Starting with the nth element, we learned how to return a new list from a list of integers, starting with the nth element and ending with the last element.

We’ll do this by solving a coding test problem, reflecting on the problem we solved, and learning about other ways to solve it.

Let’s start with the problem

Problem

Given an integer list num_list and an integer n, complete the solution function so that it returns a list containing all elements from the nth to the last element.

Example input and output

num_list: [2, 1, 6]

n: 3

result: [6]

My solution to the problem

class Solution {
    public int[] solution(int[] num_list, int n) {
        int[] answer = new int[num_list.length - n + 1];
        for(int i = n - 1; i < num_list.length; i++){
            answer[i - n + 1] = num_list[i];
        }
        } return answer;
    }
}

Solution Description

The solution method inside the Solution class takes two parameters.

The first parameter is an array of integers called num_list, and the second parameter is an integer called n.

Define the size of the array: Size a new array named answer by calculating the length from the nth to the last element of num_list.

The size of the array will be num_list.length - n + 1.

Copy through a loop: Use a for loop to copy the values in num_list from the nth element to the last element into the answer array.

The i variable starts at n - 1 and iterates until it is less than num_list.length, which allows us to handle zero-based indexing in Java.

Return the result: When the copying is complete, we return the answer array. This array contains the values from the nth to the last element of num_list.