Submission #201638

#	Time	Username	Problem	Language	Result	Execution time	Memory
201638		stefdasca	Nafta (COI15_nafta)	C++14	34 / 100	1093 ms	62968 KiB

nafta

#include<bits/stdc++.h>
#define god dimasi5eks
#pragma GCC optimize("O3")
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define mod 1000000007
#define dancila 3.14159265359
#define eps 1e-9

// #define fisier 1

using namespace std;

typedef long long ll;

int n, m, sum[3002][3002], sum2[3002][3002];

char mat[3002][3002];

int ox[] = {-1, 0, 1, 0};
int oy[] = {0, 1, 0, -1};

int cum[3002], finish[3002];

int dp[3002][3002], sp[3002][3002], opt[3002][3002];

int cost(int a, int b)
{
    return sp[a][b];
}
void divide(int st, int dr, int optst, int optdr, int pz)
{
    if(st > dr || optst > optdr)
        return;
    int mid = (st + dr) / 2;
    int wht = mid;
    dp[pz][mid] = dp[pz-1][mid];
    //cout << "start " << st << " " << dr << " " << mid << " " << optst << " " << optdr << '\n';
    for(int i = min(mid, optst); i <= min(mid, optdr); ++i)
        if(dp[pz-1][i] + cum[mid] - cost(i, mid) > dp[pz][mid])
        {
          //  cout << "state " << i << " " << mid << " " << cum[mid] << " " << cost(i, mid) << '\n';
            dp[pz][mid] = dp[pz-1][i] + cum[mid] - cost(i, mid);
            wht = i;
        }
  //  cout << "finish " << mid << " " << pz << " " << dp[pz][mid] << " " << cum[mid] << " " << wht << '\n';
    divide(st, mid-1, optst, wht, pz);
    divide(mid+1, dr, wht, optdr, pz);
}
int main()
{

    #ifdef fisier
        ifstream f("input.in");
        ofstream g("output.out");
    #endif

    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    cin >> n >> m;
    for(int i = 1; i <= n; ++i)
        cin >> (mat[i] + 1);
    int acm = 0;
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= m; ++j)
            if(mat[i][j] >= '0' && mat[i][j] <= '9')
            {
                int L = j, R = j;
                int tot = (mat[i][j] - '0');
                deque<pair<int, int> > d;
                d.pb({i, j});
                mat[i][j] = '.';
                while(!d.empty())
                {
                    pair<int, int> nod = d[0];
                    L = min(L, nod.se);
                    R = max(R, nod.se);
                    d.pop_front();
                    for(int x = 0; x <= 3; ++x)
                    {
                        int new_x = nod.fi + ox[x];
                        int new_y = nod.se + oy[x];
                        if(new_x == 0 || new_y == 0 || new_x == n+1 || new_y == m+1)
                            continue;
                        if(mat[new_x][new_y] == '.')
                            continue;
                        tot += (mat[new_x][new_y] - '0');
                        mat[new_x][new_y] = '.';
                        d.pb({new_x, new_y});
                    }
                }
                sum[L][R] += tot;
                acm += tot;
            }
    for(int i = 1; i <= m; ++i)
        for(int j = i; j <= m; ++j)
            cum[i] += sum[i][j], cum[j+1] -= sum[i][j], finish[j] += sum[i][j];
    for(int i = 1; i <= m; ++i)
        for(int j = m; j >= 1; --j)
            sum2[i][j] = sum[i][j] + sum2[i][j+1];
    for(int i = 1; i <= m; ++i)
        for(int j = m; j >= 1; --j)
        {
            sp[i][j] = sum2[i][j] + sp[i-1][j];
        //    cout << i << " " << j << " " << sp[i][j] << '\n';
        }
    for(int i = 1; i <= m; ++i)
    {
        cum[i] += cum[i-1];
        dp[1][i] = cum[i];
    }
    /*
    for(int i = 2; i <= m; ++i)
    {
      //  cout << "new " << i << '\n';
        divide(1, m, 1, m, i);
    }
    */
    for(int i = 2; i <= m; ++i)
        for(int j = 1; j <= m; ++j)
        {
            for(int k = 1; k < j; ++k)
            {
                if(dp[i-1][k] - cost(k, j) + cum[j] > dp[i][j])
                {
                    dp[i][j] = max(dp[i][j], dp[i-1][k] - cost(k, j) + cum[j]);
                    opt[i][j] = k;
                }
            }
            if(dp[i-1][j] > dp[i][j])
            {
                dp[i][j] = dp[i-1][j];
                opt[i][j] = j;
            }
            assert(opt[i][j] >= opt[i][j-1]);
        }
    int ans = 0;
    for(int i = 1; i <= m; ++i)
    {
        for(int j = 1; j <= m; ++j)
            ans = max(ans, dp[i][j]);
        cout << ans << '\n';
    }
    return 0;
}

• Subtask 1: 11 / 11
• Subtask 2: 23 / 23
• Subtask 3: 0 / 66