answer1.cpp

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

bool isSubset(vector<char> A, vector<char> B);

bool isSubset(vector<char> A, vector<char> B) {
    bool map[26] = { false };
    for(char inA : A)
        map[(inA - '0')] = true;
    
    for(char inB : B)
        if(!map[(inB - '0')])
            return false;

    return true;
}

int main() {
    vector<char> A = {'A', 'B', 'C', 'D', 'E'};
    vector<char> B = {'A', 'A', 'D', 'E'};
    cout << "isSubset(A,B) = " << isSubset(A,B) << endl;
    // Computational complexity is O(n) since building the map require looping n times to build and search
    return 0;
}