DSA-Practice/UnionOfTwoSortedArrays.cpp at main · TheMahirK/DSA-Practice · GitHub

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#include <iostream>
#include <set>
using namespace std;

void display(vector<int> &arr)
{
    for(auto x : arr)
    {
        cout << x << ' ';
    }
    cout << endl;
}


vector<int> unionOfTwoSortedArrays1(vector<int> &arr1, vector<int> &arr2)
{
    set<int> s;
    for(int i=0; i<arr1.size(); i++)
    {
        s.insert(arr1[i]);
    }
    for(int i=0; i<arr2.size(); i++)
    {
        s.insert(arr2[i]);
    }
    vector<int> result;
    for(auto x : s)
    {
        result.push_back(x);
    }
    return result;

}

vector<int> unionOfTwoSortedArrays2(vector<int> &arr1, vector<int> &arr2)
{
    int n1 = arr1.size();
    int n2 = arr2.size();
    int i = 0, j = 0;
    vector<int> result;
    while(i<n1 && j<n2)
    {
        // For arr1 elements
        if(arr1[i] <= arr2[j])
        {
            if(result.size() == 0 || result.back() != arr1[i])
            {
                result.push_back(arr1[i]);
            }
            i++;
        }

        // For arr2 elements
        if(arr2[j] <= arr1[i])
        {
            if(result.size() == 0 || result.back() != arr2[j])
            {
                result.push_back(arr2[j]);
            }
            j++;
        }
    }

    // For remaining elements
    while(i < n1)
    {
        if(result.size() == 0 || result.back() != arr1[i])
        {
            result.push_back(arr1[i]);
        }
        i++;
    }
    while(j < n2)
    {
        if(result.size() == 0 || result.back() != arr2[j])
        {
            result.push_back(arr2[j]);
        }
        j++;
    }
    return result;
}

int main()
{
    vector<int> arr1 = {0,1,3,5,7,8,9,11,12,13};
    vector<int> arr2 = {0,2,4,6,8,9,12,14,16};

    display(arr1);
    display(arr2);

    vector<int> arr3 = unionOfTwoSortedArrays2(arr1,arr2);
    display(arr3);

    return 0;
}