Submission #379118

#	Time	Username	Problem	Language	Result	Execution time	Memory
379118		dannyboy20031204	Chessboard (IZhO18_chessboard)	C++17	8 / 100	25 ms	3564 KiB

chessboard

#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define z return 0;
using namespace std;
const int N = 1e5 + 5, inf = 1e9 + 1; //
int main(){
    ios::sync_with_stdio(0), cin.tie(0);
    int n, k;
    cin >> n >> k;
    int a[k], b[k], c[k], d[k];
    for (int i = 0; i < k; i++) cin >> a[i] >> b[i] >> c[i] >> d[i];
    ll ans = inf;
    for (int l = 1; l < n; l++){
        if (n % l) continue;
        int l2 = n / l;
        ll tmp = 1ll * l * l * (1ll * l2 * l2 / 2), tmp2 = tmp + 1ll * l * l * (l2 % 2);
        swap(tmp, tmp2);
        int d0[n + 1]{}, d1[n + 1]{}, pre[n + 1]{};
        for (int i = 1; i <= n; i++){
            pre[i] = pre[i - 1] + (i % (l * 2) > 0 and i % (l * 2) <= l);
        }
        for (int i = 0; i < k; i++){
            int p = pre[c[i]] - pre[a[i] - 1], p2 = c[i] - a[i] + 1 - p;
            d0[b[i]] += p;
            d0[d[i] + 1] -= p;
            d1[b[i]] += p2;
            d1[d[i] + 1] -= p2;
        }
        ll pre0 = 0, pre1 = 0;
        for (int i = 1; i <= n; i++){
            pre0 += d0[i], pre1 += d1[i];
            if (i % (l * 2) > 0 and i % (l * 2) <= l){
                tmp += pre1 - pre0;
                tmp2 += pre0 - pre1;
            }
            else{
                tmp2 += pre1 - pre0;
                tmp += pre0 - pre1;
            }
        }
        ans = min({ans, tmp, tmp2});
    }
    cout << ans;
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 8
• Subtask 3: 0 / 15
• Subtask 4: 0 / 16
• Subtask 5: 0 / 23
• Subtask 6: 0 / 30