AcWing 3655. 楼层

#include <iostream>
using namespace std;
int main() {
    int T, n, x;
    cin >> T;
    while (T--) {
        cin >> n >> x;
        cout << (n <= 2 ? 1 : (n - 3 + x) / x + 1) << endl;
    }
    return 0;
}