oj.uz

Submission #552582

# Submission time Handle Problem Language Result Execution time Memory
552582 2022-04-23T11:23:35 Z SmolBrain Portals (BOI14_portals) C++17
70 / 100
 1000 ms 47812 KB 
// Om Namah Shivaya
// GM in 101 days

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define endl '\n'
#define pb push_back
#define conts continue
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define ff first
#define ss second
#define ceil2(x,y) ((x+y-1) / (y))
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#ifndef ONLINE_JUDGE
#define debug(x) cout << #x <<" = "; print(x); cout << endl
#else
#define debug(x)
#endif

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

bool iseven(ll n) {if ((n & 1) == 0) return true; return false;}

void print(ll t) {cout << t;}
void print(int t) {cout << t;}
void print(string t) {cout << t;}
void print(char t) {cout << t;}
void print(double t) {cout << t;}
void print(ld t) {cout << t;}

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(pair <T, V> p) {cout << "{"; print(p.ff); cout << ","; print(p.ss); cout << "}";}
template <class T> void print(vector <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(set <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(multiset <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T, class V> void print(map <T, V> v) {cout << "[ "; for (auto i : v) {print(i); cout << " ";} cout << "]";}
template<typename T> void amin(T &a, T b) { a = min(a, b); }
template<typename T> void amax(T &a, T b) { a = max(a, b); }

void usaco(string filename) {
    freopen((filename + ".in").c_str(), "r", stdin);
    freopen((filename + ".out").c_str(), "w", stdout);
}

const int MOD = 1e9 + 7;
const int maxn = 1e5 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = ll(1e18) + 5;

int nxtleft[1005][1005], nxtright[1005][1005], nxtup[1005][1005], nxtdown[1005][1005];
bool vis[1005][1005];
int dis[1005][1005];
int dx[4] = { -1, 1, 0, 0};
int dy[4] = {0, 0, -1, 1};

void solve(int test_case)
{
    // referred to: https://github.com/tmwilliamlin168/CompetitiveProgramming/blob/master/BtOI/14-Portals.cpp and the official editorial code
    // initially got WA cuz i misunderstood the problem statement (more like overlooked a particular case)

    int n, m; cin >> n >> m;
    vector<vector<char>> a(n + 5, vector<char>(m + 5, '#'));
    rep1(i, n) rep1(j, m) cin >> a[i][j];

    rep1(i, n) {
        stack<ll> st;
        rep(j, m + 2) {
            if (a[i][j] == '#') {
                while (!st.empty()) {
                    nxtright[i][st.top()] = j;
                    st.pop();
                }
            }
            else {
                st.push(j);
            }
        }

        while (!st.empty()) st.pop();

        rev(j, m + 1, 0) {
            if (a[i][j] == '#') {
                while (!st.empty()) {
                    nxtleft[i][st.top()] = j;
                    st.pop();
                }
            }
            else {
                st.push(j);
            }
        }
    }

    rep1(j, m) {
        stack<ll> st;

        rep(i, n + 2) {
            if (a[i][j] == '#') {
                while (!st.empty()) {
                    nxtdown[st.top()][j] = i;
                    st.pop();
                }
            }
            else {
                st.push(i);
            }
        }

        while (!st.empty()) st.pop();

        rev(i, n + 1, 0) {
            if (a[i][j] == '#') {
                while (!st.empty()) {
                    nxtup[st.top()][j] = i;
                    st.pop();
                }
            }
            else {
                st.push(i);
            }
        }
    }

    pii start, end;
    rep1(i, n) rep1(j, m) {
        if (a[i][j] == 'S') start = {i, j};
        else if (a[i][j] == 'C') end = {i, j};
    }

    queue<pii> q;
    rep(i, n + 2) rep(j, m + 2) {
        if (a[i][j] != '#') conts;
        q.push({i, j});
        vis[i][j] = 1;
        dis[i][j] = 0;
    }

    while (!q.empty()) {
        auto [i, j] = q.front();
        q.pop();

        rep(x, 4) {
            int i2 = i + dx[x], j2 = j + dy[x];
            if (i2 < 0 or i2 > n + 1 or j2 < 0 or j2 > m + 1) conts;
            if (vis[i2][j2]) conts;

            q.push({i2, j2});
            vis[i2][j2] = 1;
            dis[i2][j2] = dis[i][j] + 1;
        }
    }

    priority_queue< array<int, 3>, vector<array<int, 3>>, greater<array<int, 3>> > pq;
    pq.push({0, start.ff, start.ss});
    memset(vis, 0, sizeof vis);

    while (!pq.empty()) {
        auto [cost, i, j] = pq.top();
        pq.pop();

        if (vis[i][j]) conts;
        vis[i][j] = 1;

        if (i == end.ff and j == end.ss) {
            cout << cost << endl;
            return;
        }

        rep(x, 4) {
            int i2 = i + dx[x], j2 = j + dy[x];
            if (i2 < 0 or i2 > n + 1 or j2 < 0 or j2 > m + 1) conts;
            if (vis[i2][j2]) conts;
            if (a[i2][j2] == '#') conts;

            pq.push({cost + 1, i2, j2});
        }

        int min_dis_to_wall = dis[i][j];

        pq.push({cost + min_dis_to_wall, i, nxtleft[i][j] + 1});
        pq.push({cost + min_dis_to_wall, i, nxtright[i][j] - 1});
        pq.push({cost + min_dis_to_wall, nxtup[i][j] + 1, j});
        pq.push({cost + min_dis_to_wall, nxtdown[i][j] - 1, j});
    }
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;
    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Compilation message

portals.cpp: In function 'void usaco(std::string)':
portals.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |     freopen((filename + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
portals.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen((filename + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1356 KB Output is correct
2 Correct 1 ms 1492 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Correct 1 ms 1364 KB Output is correct
5 Correct 1 ms 1484 KB Output is correct
6 Correct 1 ms 1492 KB Output is correct
7 Correct 1 ms 1480 KB Output is correct
8 Correct 1 ms 1492 KB Output is correct
9 Correct 1 ms 1356 KB Output is correct
10 Correct 1 ms 1360 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1484 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Correct 1 ms 1364 KB Output is correct
5 Correct 1 ms 1484 KB Output is correct
6 Correct 1 ms 1492 KB Output is correct
7 Correct 1 ms 1480 KB Output is correct
8 Correct 1 ms 1492 KB Output is correct
9 Correct 4 ms 2380 KB Output is correct
10 Correct 4 ms 2472 KB Output is correct
11 Correct 2 ms 2260 KB Output is correct
12 Correct 2 ms 2260 KB Output is correct
13 Correct 3 ms 2256 KB Output is correct
14 Correct 1 ms 1360 KB Output is correct
15 Correct 3 ms 2388 KB Output is correct
16 Correct 1 ms 1364 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1484 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Correct 1 ms 1488 KB Output is correct
5 Correct 17 ms 5544 KB Output is correct
6 Correct 25 ms 5572 KB Output is correct
7 Correct 19 ms 5588 KB Output is correct
8 Correct 10 ms 5592 KB Output is correct

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1492 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Correct 1 ms 1364 KB Output is correct
5 Correct 1 ms 1488 KB Output is correct
6 Correct 1 ms 1476 KB Output is correct
7 Correct 1 ms 1492 KB Output is correct
8 Correct 1 ms 1492 KB Output is correct
9 Correct 3 ms 2388 KB Output is correct
10 Correct 2 ms 2388 KB Output is correct
11 Correct 2 ms 2260 KB Output is correct
12 Correct 2 ms 2260 KB Output is correct
13 Correct 3 ms 2260 KB Output is correct
14 Correct 19 ms 5540 KB Output is correct
15 Correct 29 ms 5544 KB Output is correct
16 Correct 19 ms 5460 KB Output is correct
17 Correct 23 ms 5460 KB Output is correct
18 Correct 27 ms 5588 KB Output is correct
19 Correct 6 ms 5540 KB Output is correct
20 Correct 17 ms 6988 KB Output is correct
21 Correct 17 ms 5460 KB Output is correct
22 Correct 19 ms 5460 KB Output is correct
23 Correct 21 ms 5460 KB Output is correct
24 Correct 57 ms 6180 KB Output is correct
25 Correct 1 ms 1356 KB Output is correct
26 Correct 3 ms 2388 KB Output is correct
27 Correct 1 ms 1364 KB Output is correct
28 Correct 9 ms 5540 KB Output is correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1492 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Correct 1 ms 1364 KB Output is correct
5 Correct 1 ms 1476 KB Output is correct
6 Correct 1 ms 1492 KB Output is correct
7 Correct 1 ms 1492 KB Output is correct
8 Correct 1 ms 1492 KB Output is correct
9 Correct 3 ms 2488 KB Output is correct
10 Correct 3 ms 2464 KB Output is correct
11 Correct 3 ms 2256 KB Output is correct
12 Correct 3 ms 2260 KB Output is correct
13 Correct 3 ms 2260 KB Output is correct
14 Correct 19 ms 5500 KB Output is correct
15 Correct 23 ms 5532 KB Output is correct
16 Correct 19 ms 5536 KB Output is correct
17 Correct 24 ms 5516 KB Output is correct
18 Correct 28 ms 5592 KB Output is correct
19 Correct 6 ms 5460 KB Output is correct
20 Correct 16 ms 6988 KB Output is correct
21 Correct 18 ms 5480 KB Output is correct
22 Correct 20 ms 5460 KB Output is correct
23 Correct 27 ms 5460 KB Output is correct
24 Correct 737 ms 27044 KB Output is correct
25 Execution timed out 1084 ms 47812 KB Time limit exceeded
26 Halted 0 ms 0 KB -