Merging Two Sorted Lists - Amazon Top Interview Questions

Problem Statement :

Given two lists of integers a and b sorted in ascending order, merge them into one large sorted list.


0 ≤ n ≤ 200,000 where n is the length of a
0 ≤ m ≤ 200,000 where m is the length of b

Example 1

a = [5, 10, 15]
b = [3, 8, 9]

[3, 5, 8, 9, 10, 15]

Solution :


                        Solution in C++ :

vector<int> solve(vector<int>& a, vector<int>& b) {
    int an = a.size(), bn=b.size();
    int left = 0, right = 0, n=an+bn, k=0;
    vector<int> ans(n);

    while(left<an && right<bn){
        if(a[left]<b[right]) ans[k++] = a[left++];
        else ans[k++] = b[right++];
    while(left<an) ans[k++] = a[left++];
    while(right<bn) ans[k++] = b[right++];
    return ans;

                        Solution in Java :

import java.util.*;

class Solution {
    public int[] solve(int[] a, int[] b) {
        int i = 0;
        int j = 0;
        int[] result = new int[a.length + b.length];
        int index = 0;
        while (i < a.length || j < b.length) {
            int num1 = i < a.length ? a[i] : Integer.MAX_VALUE;
            int num2 = j < b.length ? b[j] : Integer.MAX_VALUE;
            if (num1 < num2) {
                result[index++] = num1;
            } else {
                result[index++] = num2;
        return result;

                        Solution in Python : 
class Solution:
    def solve(self, l, r):
        li, ri, result = 0, 0, []
        while li < len(l) and ri < len(r):
            if l[li] <= r[ri]:
                li += 1
                ri += 1

        return result + l[li:] + r[ri:]

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