Submission #516348

#	Time	Username	Problem	Language	Result	Execution time	Memory
516348		Jomnoi	Orchard (NOI14_orchard)	C++17	25 / 25	332 ms	49172 KiB

orchard

#include <bits/stdc++.h>
#define DEBUG 0
using namespace std;

const int INF = 1e9 + 7;

vector <vector <int>> a;
vector <int> dp;

int get(int x1, int x2, int y1, int y2) {
    return a[x2][y2] - a[x1 - 1][y2] - a[x2][y1 - 1] + a[x1 - 1][y1 - 1];
}

int main() {
    int n, m;
    scanf(" %d %d", &n, &m);
    a.resize(n + 10, vector <int> (m + 10));
    dp.resize(m + 10);

    int sum = 0;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            scanf(" %d", &a[i][j]);

            if(a[i][j] == 0) {
                a[i][j] = 1;
            }
            else {
                sum++;
                a[i][j] = -1;
            }
            a[i][j] += a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1];
        }
    }

    int ans = INF;
    dp[m + 1] = INF;
    for(int i = 1; i <= n; i++) {
        for(int j = i; j <= n; j++) {
            for(int k = m; k >= 1; k--) {
                dp[k] = min(dp[k + 1], get(i, j, 1, k));
            }

            if(DEBUG) {
                cout << "Debugging : " << i << " " << j << endl;
                for(int k = 1; k <= m; k++) {
                    cout << dp[k] << " ";
                }
                cout << endl;
            }

            for(int k = 1; k <= m; k++) {
                ans = min(ans, sum + dp[k] - get(i, j, 1, k - 1));
            }
        }
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

orchard.cpp: In function 'int main()':
orchard.cpp:16:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     scanf(" %d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~~
orchard.cpp:23:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |             scanf(" %d", &a[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 5 / 5
• Subtask 4: 3 / 3
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5