Challenges_to_first_occurance.cpp

#include <bits/stdc++.h>
using namespace std;

long solveChallenges(int N, int arr[], int K, int challenges[]) {
    // Write your code here
    long ans = 0;

    for (int i = 0; i < K; i++) {
        int low = 0, high = N - 1;
        long tempRes = -1;

        while (low <= high) {
            int mid = (low + high) / 2;

            if (arr[mid] > challenges[i])
                high = mid - 1;

            else if (arr[mid] < challenges[i])
                low = mid + 1;

            else {
                tempRes = mid;
                high = mid - 1;
            }
        }

        ans += tempRes;
    }

    return ans;
}

int main() {
    int i, k, size = 0, size1 = 0;
    cin >> size;
    int a[size];
    for (i = 0; i < size; i++)
        cin >> a[i];

    cin >> size1;
    int b[size1];
    for (i = 0; i < size1; i++)
        cin >> b[i];

    long final = solveChallenges(size, a, size1, b);
    cout << final;

    return 0;
}