Submission #238226

#	Time	Username	Problem	Language	Result	Execution time	Memory
238226		Vimmer	Retro (COCI17_retro)	C++14	49 / 100	191 ms	220412 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;


ll f[301][301][301], n, m;

vector <char> ans;

string s[301];

vector <char> bst[301][301];

bool mk[301][301][301], mkr[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;
}

priority_queue <array <int, 3> > qr;

void solve(int i, int j, int b, int len)
{
    if (mk[i][j][b]) return;

    mk[i][j][b] = 1;

    if (i == n - 1) return;

    if (s[i][j] == '(') {b--; len--; }

    if (s[i][j] == ')') {b++; len--; }

    for (int a = -1; a <= 1; a++)
    {
        int nb = b, nlen = len, jr = j + a;

        if (jr < 0 || jr == m || s[i + 1][jr] == '*') continue;

        if (nb == -1) continue;

        if (f[i + 1][jr][nb] == nlen) solve(i + 1, jr, nb, nlen);
    }

}
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);

    cin >> n >> m;

    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;}

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

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

    ll I = -1, J, K = -1;

    for (int i = n - 1; i > 0; i--)
        for (int j = 0; j < m; j++)
          for (int st = 0; st <= n - i - 1; st++)
            {
                if (f[i][j][st] == -1 || s[i][j] == '*') continue;

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

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

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

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

    for (int i = 0; i < 301; i++)
        for (int j = 0; j < 301; j++)
            if (K < f[i][j][0]) {I = i; J = j; K = f[i][j][0];}

    for (int i = 0; i < 301; i++)
        for (int j = 0; j < 301; j++)
          if (f[i][j][0] == K) solve(i, j, 0, K);

    cout << K << endl;

    qr.push({0, sx, sy});

    while (sz(qr) > 0)
    {
        int tp = qr.top()[0], i = qr.top()[1], j = qr.top()[2];

        qr.pop();

        if (tp == 1) bst[i][j].pb('(');

        if (tp == 2) bst[i][j].pb(')');

        if (sz(bst[i][j]) == K)
        {
            if (sz(ans) == 0 || low(bst[i][j], ans)) ans = bst[i][j];

            continue;
        }

        int len = sz(bst[i][j]), b = 0;

        for (auto it : bst[i][j])
            if (it == '(') b++;

        b = b + b - sz(bst[i][j]);

        for (int a = -1; a <= 1; a++)
        {
            int jr = j + a, nlen = len, nb = b, tp = 0;

            if (jr < 0 || jr == m || s[i - 1][jr] == '*' || mkr[i - 1][jr]) continue;

            if (s[i - 1][jr] == '(') {tp = 1; nb++; nlen++;}

            if (s[i - 1][jr] == ')') {tp = 2; nb--; nlen++;}

            if (nb == -1) continue;

            if (mk[i - 1][jr][nb] && f[i - 1][jr][nb] == nlen) {mkr[i - 1][jr] = 1; bst[i - 1][jr] = bst[i][j]; qr.push({tp, i - 1, jr}); }
        }
    }

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

Compilation message (stderr)

retro.cpp: In function 'int main()':
retro.cpp:97:8: warning: variable 'I' set but not used [-Wunused-but-set-variable]
     ll I = -1, J, K = -1;
        ^
retro.cpp:97:16: warning: variable 'J' set but not used [-Wunused-but-set-variable]
     ll I = -1, J, K = -1;
                ^
retro.cpp:95:18: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]
     f[sx][sy][0] = 0;
     ~~~~~~~~~~~~~^~~
retro.cpp:95:18: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 49 / 100