Submission #237360

#	Time	Username	Problem	Language	Result	Execution time	Memory
237360		Vimmer	Retro (COCI17_retro)	C++14	70 / 100	323 ms	112256 KiB

retro

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>

#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#pragma GCC optimize("Ofast")
//#pragma GCC optimize("fast-math")
//#pragma GCC optimize("no-stack-protector")

#define F first
#define S second
#define sz(x) int(x.size())
#define pb push_back
#define N 100001
#define M ll(1e9 + 7)
#define inf 1e9 + 1e9

using namespace std;
//using namespace __gnu_pbds;

typedef long double ld;
typedef long long ll;
typedef short int si;
typedef array <int, 2> a2;

//typedef tree <int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



vector <char> ans, ndp[101][32][32], dp[101][32][32];

bool nmk[101][32][32], mk[101][32][32];

int f[301][301][301];

bool low(vector <char> &a, vector <char> &b)
{
    for (int i = 0; i < sz(a); i++)
    {
        if (a[i] == b[i]) continue;

        return a[i] == '(';
    }

    return 0;
}

int main()
{
    //freopen("input.txt", "r", stdin); //freopen("output4.txt", "w", stdout);

    ios_base::sync_with_stdio(0); istream::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int n, m;

    cin >> n >> m;

    string s[n];

    for (int i = 0; i < n; i++) cin >> s[i];

    int sx, sy;

    for (int i = 0; i < m; i++)
        if (s[n - 1][i] == 'M') {sx = n - 1; sy = i; break;}

    if (n <= 100)
    {
        mk[sy][0][0] = 1;

        for (int i = n - 1; i >= 0; i--)
         {
            for (int j = 0; j < m; j++)
              for (int k = 0; k < min(30, n - i); k++)
                for (int kr = 0; kr <= k; kr++)
                {
                    if (!mk[j][k][kr]) continue;

                    if (k == kr && (k + kr > sz(ans) || (k + k == sz(ans) && low(dp[j][k][kr], ans)))) ans = dp[j][k][kr];

                    if (s[i][j] == '*' || i == 0) continue;

                    for (int a = -1; a <= 1; a++)
                        if (a + j >= 0 && a + j < m && (k != kr || s[i - 1][j + a] != ')'))
                        {
                            int nw = kr, nk = k;

                            vector <char> nr = dp[j][k][kr];

                            if (s[i - 1][j + a] == '(') {nr.pb('('); nk++;}

                            if (s[i - 1][j + a] == ')') {nr.pb(')'); nw++;}

                            if (!nmk[j + a][nk][nw] || low(nr, ndp[j + a][nk][nw])) {nmk[j + a][nk][nw] = 1; ndp[j + a][nk][nw] = nr;}
                        }
                }

            for (int j = 0; j < m; j++)
              for (int k = 0; k <= min(31, n - i); k++)
                for (int kr = 0; kr <= k; kr++) {dp[j][k][kr] = ndp[j][k][kr]; ndp[j][k][kr].clear(); mk[j][k][kr] = nmk[j][k][kr]; nmk[j][k][kr] = 0;}

        }
        cout << sz(ans) << endl;

        for (auto it : ans) cout << it;

        exit(0);
    }

    memset(f, -1, sizeof(f));

    f[sx][sy][0] = 0;

    int I = -1, J, K;

    for (int i = n - 1; i > 0; i--)
        for (int j = 0; j < m; j++)
          for (int k = 0; k <= n - i - 1; k++)
            {
                if (f[i][j][k] == k && (I == -1 || K + K < k + k)) {I = i; J = j; K = k;}

                if (f[i][j][k] == -1 || s[i][j] == '*') continue;

                for (int a = -1; a <= 1; a++)
                    if (a + j >= 0 && a + j < m && (f[i][j][k] < k || s[i - 1][j + a] != ')'))
                    {
                        int nw = f[i][j][k], nk = k;

                        if (s[i - 1][j + a] == '(') nk++;

                        if (s[i - 1][j + a] == ')') nw++;

                        if (f[i - 1][j + a][nk] < nw) f[i - 1][j + a][nk] = nw;

                    }
            }

    for (int j = 0; j < m; j++)
        for (int k = 0; k <= n; k++)
          if (f[0][j][k] == k && (I == -1 || K + K < k + k)) {I = 0; J = j; K = k;}

    if (I == -1) cout << 0 << endl;
     else
     {
         cout << K + K << endl;

         int val = K;

         vector <char> g; g.clear();

         while (I != n - 1)
         {
                int pos = -1;

                for (int a = -1; a <= 1; a++)
                  if (a + J < m && a + J >= 0 && f[I + 1][a + J][K] == val && s[I + 1][a + J] != '#') pos = a + J;

                if (pos == -1)
                {
                    if (s[I][J] == ')')
                    {
                        g.pb(')');

                        val--;

                        for (int a = -1; a <= 1; a++)
                            if (a + J < m && a + J >= 0 && f[I + 1][a + J][K] == val && s[I + 1][a + J] != '#') pos = a + J;
                    }
                    else
                    {
                        g.pb('(');

                        K--;

                        for (int a = -1; a <= 1; a++)
                            if (a + J < m && a + J >= 0 && f[I + 1][a + J][K] == val && s[I + 1][a + J] != '#') pos = a + J;
                    }
                }

                J = pos;

                I++;
         }

         for (int i = sz(g) - 1; i >= 0; i--) cout << g[i];
     }
}

Compilation message (stderr)

retro.cpp: In function 'int main()':
retro.cpp:121:58: warning: 'K' may be used uninitialized in this function [-Wmaybe-uninitialized]
                 if (f[i][j][k] == k && (I == -1 || K + K < k + k)) {I = i; J = j; K = k;}
                                                    ~~~~~~^~~~~~~
retro.cpp:113:18: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
     f[sx][sy][0] = 0;
     ~~~~~~~~~~~~~^~~
retro.cpp:113:18: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 70 / 100