696 - How Many Knights

#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define endl '\n'
#define sz(x) int(x.size())
#define all(x) x.begin(), x.end()

int main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    int n, m;
    while (scanf("%d %d", &n, &m), n || m) {
        int ans = (((n + 1) / 2) * ((m + 1) / 2)) + ((n / 2) * (m / 2));
        if (min(n, m) == 1) ans = max(ans, max(n, m));
        else if (min(n, m) == 2) ans = max(ans, ((max(n, m) + 2) / 4) * 4 + 2 * (max(n, m) % 4 == 1));
        printf("%d knights may be placed on a %d row %d column board.\n", ans, n, m);
    }
}