Submission #236071

#	Time	Username	Problem	Language	Result	Execution time	Memory
236071		kartel	Portal (COCI17_portal)	C++14	96 / 120	37 ms	11776 KiB

portal

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define pb push_back
#define N +100500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e9)
#define el '\n'
#define pii pair <int, int>
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less_equal <int> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef long double ld;

struct step{
    int x, y, st;

    step(int x, int y, int st) : x(x), y(y), st(st) {};
};

queue <step *> q;
int mrk[505][505];
char c[505][505];
int Left[505][505], up[505][505], Right[505][505], down[505][505], i, j, n, m, ans, found, x, y, sx, sy, ex, ey;

void get(int &x, int &y, int &st)
{
    x = q.front() -> x;
    y = q.front() -> y;
    st = q.front() -> st;
    q.pop();
}

void put(int x, int y, int st)
{
    if (x == ex && y == ey) {ans = min(ans, st); return;}
    q.push(new step(x, y, st));
    mrk[x][y] = 1;
}

void PortalToLeft(int x, int y, int st)
{
    if (Right[x][y] != y + 1 && up[x][y] != x - 1 && down[x][y] != x + 1 && !found) return;
    int cx = x;
    int cy = Left[x][y] + 1;

    if (mrk[cx][cy]) return;

    put(cx, cy, st + 1);
}

void PortalToRight(int x, int y, int st)
{
    if (Left[x][y] != y - 1 && up[x][y] != x - 1 && down[x][y] != x + 1) return;
    int cx = x;
    int cy = Right[x][y] - 1;

    if (mrk[cx][cy]) return;

    put(cx, cy, st + 1);
}

void PortalToUp(int x, int y, int st)
{
    if (Right[x][y] != y + 1 && Left[x][y] != y - 1 && down[x][y] != x + 1) return;


    int cx = up[x][y] + 1;
    int cy = y;
//    cerr << x << " " << y << " " << cx << " " << cy << el;

    if (mrk[cx][cy]) return;

    put(cx, cy, st + 1);
}

void PortalToDown(int x, int y, int st)
{
    if (Right[x][y] != y + 1 && up[x][y] != x - 1 && Left[x][y] != y - 1) return;
    int cx = down[x][y] - 1;
    int cy = y;

    if (mrk[cx][cy]) return;

    put(cx, cy, st + 1);
}

void putall(int x, int y, int st)
{
    int steps[4][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

    for (int i = 0; i < 4; i++)
    {
        int cx = x + steps[i][0];
        int cy = y + steps[i][1];

        if (cx < 1 || cy < 1 || cx > n || cy > m || mrk[cx][cy]) continue;

        put(cx, cy, st + 1);
    }

    if (found) return;

    PortalToLeft(x, y, st);
    PortalToRight(x, y, st);
    PortalToUp(x, y, st);
    PortalToDown(x, y, st);
}

int main()
{
    srand(time(0));
    ios_base::sync_with_stdio(0);
    iostream::sync_with_stdio(0);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

//    in("input.txt");
//    out("output.txt");

    cin >> n >> m;
    for (i = 1; i <= n; i++)
    {
        for (j = 1; j <= m; j++)
        {
            cin >> c[i][j];

            if (c[i][j] == 'C') sx = i, sy = j;
            if (c[i][j] == 'F') ex = i, ey = j;

            if (c[i][j] == '#') mrk[i][j] = 1;
                           else mrk[i][j] = 0;
        }
    }

    for (i = 1; i <= n; i++)
    {
        for (j = 1; j <= m; j++)
        {
            if (c[i][j] == '#') Left[i][j] = j;
                           else Left[i][j] = Left[i][j - 1];
        }
        for (j = m; j >= 1; j--)
        {
            if (c[i][j] == '#') Right[i][j] = j;
                           else Right[i][j] = Right[i][j + 1];
        }
    }
    for (j = 1; j <= m; j++)
    {
        for (i = 1; i <= n; i++)
        {
            if (c[i][j] == '#') up[i][j] = i;
                           else up[i][j] = up[i - 1][j];
        }
        for (i = n; i >= 1; i--)
        {
            if (c[i][j] == '#') down[i][j] = i;
                           else down[i][j] = down[i + 1][j];
        }
    }

    ans = oo;
    put(sx, sy, 0);
    while (sz(q) && !found)
    {
        int st;
        get(x, y, st);
        putall(x, y,  st);
    }

    if (ans == oo) cout << "nemoguce";
              else cout << ans << el;
 }

//
//110000
//1100

• Subtask 1: 12 / 12
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 12 / 12
• Subtask 5: 12 / 12
• Subtask 6: 12 / 12
• Subtask 7: 12 / 12
• Subtask 8: 12 / 12
• Subtask 9: 0 / 12
• Subtask 10: 0 / 12