Submission #1136237

#	Time	Username	Problem	Language	Result	Execution time	Memory
1136237		ALTAKEXE	Robots (APIO13_robots)	C++17	0 / 100	49 ms	111936 KiB

robots

#include <bits/stdc++.h>
#define ll long long
#define ff first
#define ss second
#define INF INT_MAX * 8
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define FAR(i, a, b) for (int i = (a); i >= (b); i--)
#define all(x) (x.begin(), x.end())
const int MOD = 1e9 + 7;
using namespace std;
int n, w, h;
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
pair<int, int> m[500][500][4];
char s[501][501];
vector<pair<int, int>> g[500][500];
int cost[10][10][500][500];
pair<int, int> dfs(int x, int y, int d)
{
    if (x < 0)
        return {x + 1, y};
    if (y < 0)
        return {x, y + 1};
    if (x >= h)
        return {x - 1, y};
    if (y >= w)
        return {x, y - 1};
    if (s[x][y] == 'x')
        return {x + dx[d ^ 2], y + dy[d ^ 2]};
    if (m[x][y][d] != pair<int, int>{-1, -1})
        return m[x][y][d];
    int d2 = d;
    if (s[x][y] == 'A')
        d2 += 3, d2 &= 3;
    else if (s[x][y] == 'C')
        d2 += 1, d2 &= 3;
    m[x][y][d] = {-2, -2};
    return m[x][y][d] = dfs(x + dx[d2], y + dy[d2], d2);
}
void bfs(int u, int v)
{
    auto c = cost[u][v];
    for (int k = u + 1; k < v; k++)
        for (int i = 0; i < h; i++)
            for (int j = 0; j < w; j++)
                c[i][j] = min(c[i][j], cost[u][k][i][j] + cost[k][v][i][j]);
    queue<array<int, 3>> q;
    vector<array<int, 3>> q2;
    for (int i = 0; i < h; i++)
        for (int j = 0; j < w; j++)
            if (c[i][j] != INF)
                q2.push_back({c[i][j], i, j});
    sort(q2.begin(), q2.end(), greater<array<int, 3>>());
    while (q.size() || q2.size())
    {
        bool ok = 0;
        if (!q2.size())
            ok = 1;
        else if (q.size() && q.front()[0] < q2.back()[0])
            ok = 1;
        auto [une, x, y] = ok ? q.front() : q2.back();
        if (ok)
            q.pop();
        else
            q2.pop_back();
        for (auto [x2, y2] : g[x][y])
        {
            if (c[x2][y2] > une + 1)
            {
                c[x2][y2] = une + 1;
                q.push({c[x2][y2], x2, y2});
            }
        }
    }
}
int main()
{
    for (int i = 0; i < 500; i++)
        for (int j = 0; j < 500; j++)
            for (int d = 0; d < 4; d++)
                m[i][j][d].ff = m[i][j][d].ss = 255;
    for (int i = 0; i < 10; i++)
        for (int j = 0; j < 10; j++)
            for (int d = 0; d < 500; d++)
                for (int k = 0; k < 500; k++)
                    cost[i][j][d][k] = 51;
    for (int i = 0; i < h; i++)
    {
        scanf("%s", s[i]);
    }
    for (int i = 0; i < h; i++)
        for (int j = 0; j < w; j++)
            for (int d = 0; d < 4; d++)
                dfs(i, j, d);
    for (int i = 0; i < h; i++)
        for (int j = 0; j < w; j++)
            for (int d = 0; d < 4; d++)
                if (m[i][j][d] != pair<int, int>{-2, -2} && m[i][j][d] != pair<int, int>{i, j})
                    g[i][j].push_back(m[i][j][d]);
    for (int i = 0; i < h; i++)
        for (int j = 0; j < w; j++)
            if (isdigit(s[i][j]))
                cost[s[i][j] - '1'][s[i][j] - '0'][i][j] = 0;
    for (int i = 1; i <= n; i++)
        for (int j = 0; j <= n - i; j++)
            bfs(j, j + i);
    int ans = INF;
    for (int i = 0; i < h; i++)
        for (int j = 0; j < w; j++)
            ans = min(ans, cost[0][n][i][j]);
    cout << ((ans == INF) ? -1 : ans) << endl;
    return 0;
}

Compilation message (stderr)

robots.cpp: In function 'void bfs(int, int)':
robots.cpp:5:21: warning: integer overflow in expression of type 'int' results in '-8' [-Woverflow]
    5 | #define INF INT_MAX * 8
      |                     ^
robots.cpp:51:28: note: in expansion of macro 'INF'
   51 |             if (c[i][j] != INF)
      |                            ^~~
robots.cpp: In function 'int main()':
robots.cpp:5:21: warning: integer overflow in expression of type 'int' results in '-8' [-Woverflow]
    5 | #define INF INT_MAX * 8
      |                     ^
robots.cpp:107:15: note: in expansion of macro 'INF'
  107 |     int ans = INF;
      |               ^~~
robots.cpp:5:21: warning: integer overflow in expression of type 'int' results in '-8' [-Woverflow]
    5 | #define INF INT_MAX * 8
      |                     ^
robots.cpp:111:22: note: in expansion of macro 'INF'
  111 |     cout << ((ans == INF) ? -1 : ans) << endl;
      |                      ^~~
robots.cpp:89:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |         scanf("%s", s[i]);
      |         ~~~~~^~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40