Code: Flip the Bit (Easy Version)

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

void solve() {
    int n, k;
    cin >> n >> k;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i];
    vector<int> p(k);
    for (int i = 0; i < k; ++i) cin >> p[i];

    const int x = a[p[0] - 1];
    const int pivot = p[0];

    int leftCuts = 0;
    int prev = 0;  // b_0 = 0
    for (int i = 1; i <= pivot; ++i) {
        int bi = (i == pivot ? 0 : (a[i - 1] ^ x));
        leftCuts += (bi != prev);
        prev = bi;
    }

    int rightCuts = 0;
    prev = 0;  // b_p = 0
    for (int i = pivot; i <= n + 1; ++i) {
        int bi = 0;
        if (i >= pivot + 1 && i <= n) bi = (a[i - 1] ^ x);
        rightCuts += (bi != prev);
        prev = bi;
    }

    cout << max(leftCuts, rightCuts) << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) solve();
    return 0;
}

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

void solve() {
    int N, K;
    cin >> N >> K;
    vector<int> A(N);
    for (int i = 0; i < N; i++) {
        cin >> A[i];
    }
    int P;
    for (int i = 0; i < K; i++) {
        cin >> P;
    }
    P--;
    int nless = 0, nmore = 0;
    for (int i = 0; i + 1 <= P; i++) {
        if (A[i] != A[i + 1])
            nless++;
    }
    for (int i = P; i + 1 < N; i++) {
        if (A[i] != A[i + 1])
            nmore++;
    }
    int ans = max(nless, nmore);
    if (ans & 1)
        ans++;
    cout << ans << '\n';
}

int main() {
    ios_base::sync_with_stdio(false), cin.tie(nullptr);
    int T;
    cin >> T;
    while (T--)
        solve();
}