Submission #238214

#	Time	Username	Problem	Language	Result	Execution time	Memory
238214		Vimmer	Retro (COCI17_retro)	C++14	46 / 100	171 ms	218104 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, g;

string s[301];

bool mk[301][301][301];

bool low(vector <char> &a, vector <char> &b)
{
    for (int i = sz(a) - 1; i >= 0; i--)
    {
        if (a[i] == b[i]) continue;

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

    return 0;
}
//void rec(int i, int j, int b, int len)
//{
//    if (mk[i][j][b]) return;
//
//    mk[i][j][b] = 1;
//
//    if (i == n - 1) return;
//
//    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 (s[i + 1][jr] == '(') {nb++; nlen++;}
//
//        if (s[i + 1][jr] == ')') {nb--; nlen++;}
//
//        if (nb == -1) continue;
//
//        if (f[i + 1][jr][nb] == nlen) rec(i + 1, jr, nb, nlen);
//    }
//}


void solve(int i, int j, int b, int len)
{
//    if (mk[i][j][b]) return;
//
//    mk[i][j][b] = 1;

    if (mk[i][j][b]) return;

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

    if (i == n - 1)
    {
        if (sz(ans) == 0 || low(g, ans)) ans = g;

        return;
    }

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

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

    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;

       // cout << i + 1 << " " << jr << " " << nb << " " << nlen << " " << f[i + 1][jr][nb] << endl;

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


    if (s[i][j] == '(') g.pop_back();

    if (s[i][j] == ')') g.pop_back();

}
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) rec(i, j, 0, K)

    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;

    reverse(ans.begin(), ans.end());

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

}

Compilation message (stderr)

retro.cpp: In function 'int main()':
retro.cpp:133:8: warning: variable 'I' set but not used [-Wunused-but-set-variable]
     ll I = -1, J, K = -1;
        ^
retro.cpp:133:16: warning: variable 'J' set but not used [-Wunused-but-set-variable]
     ll I = -1, J, K = -1;
                ^
retro.cpp:131:18: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]
     f[sx][sy][0] = 0;
     ~~~~~~~~~~~~~^~~
retro.cpp:131:18: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 46 / 100