Submission #1114283

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114283		ljtunas	Patkice (COCI20_patkice)	C++14	0 / 50	2 ms	6480 KiB

patkice

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define fi first
#define se second
#define Rep(i, n)  for(int i = 1; i <= n; ++i)
#define For(i, a, b) for(int i = a; i <= b; ++i)
#define Ford(i, a, b) for(int i = a; i >= b; --i)
#define Forv(v, h) for(auto &v : h)
#define Bit(x, i) ((x) >> (i) & 1ll)
#define onbit(x, i) ((x)  (1ll << i))
#define offbit(x, i) ((x) &~ (1ll << i))
#define cnt_bit(x) __builtin_popcountll(x)
#define Log2(x) (63 - __builtin_clzll(x))
#define all(h) h.begin(), h.end()
#define reset(h, v) (memset(h, v, sizeof(h)))
#define memoryof(v) (sizeof(v) / 1024 / 1024)

using ii  = pair<int, int>;
using ull = unsigned long long;
using db  = long double;
using vi  = vector<int>;
using vvi  = vector<vi>;
using vii  = vector<ii>;

const int dx[] = {0, +1, -1, 0};
const int dy[] = {-1, 0, 0, +1};
const int MAXN = 2e3  + 10;
const int  MOD = 1e9  + 7;
const int   oo = 1e18 + 1;
const int base = 311;

template <class X, class Y> bool maximize(X &a, const Y &b) {
    if(a < b) return a = b, true;
    return false;
}

template <class X, class Y> bool minimize(X &a, const Y &b) {
    if(a > b) return a = b, true;
    return false;
}

// (x, y) -> (u, v) = Ckn(u - x, x + y - u - v);
// Ckn(k, a) * Ckn(k, b) = C(a, a + b);  (k : 1 -> min(a, b))

void fixmod(int &val) {
    if (val < 0) val += MOD*MOD;
    val %= MOD;
}


int n, m;
char a[MAXN][MAXN];
map<char, int> id;

int d[MAXN][MAXN];
ii s, t;
int trace[MAXN][MAXN];

void bfs()
{
        deque <ii> dq;
        For (i, 1, n) For (j, 1, m) d[i][j] = oo;
        d[s.fi][s.se] = 0;
        dq.push_front(s);
        while (!dq.empty()) {
                int u = dq.front().fi;
                int v = dq.front().se;
                dq.pop_front();
                For (k, 0, 3) {
                        int x = u + dx[k];
                        int y = v + dy[k];
                        if (1 <= x && x <= n && 1 <= y && y <= m) {
                            int w = 1;
                            if (id[a[u][v]] == k || a[u][v] == 'o') w = 0;
                            if (d[x][y] > d[u][v] + w)
                            {
                                    d[x][y] = d[u][v] + w;
                                    if (w) dq.push_back({x, y});
                                    else dq.push_front({x, y});
                                    trace[x][y] = k;
                            }
                        }
                }
        }
}

void Progess() {
        cin >> n >> m;
        For (i, 1, n) For (j, 1, m) {
                cin >> a[i][j];
                if (a[i][j] == 'o') s = {i, j};
                if (a[i][j] == 'x') t = {i, j};
        }
        id['<'] = 0, id['v'] = 1, id['^'] = 2, id['>'] = 3, id['.'] = 5;
        bfs();
        cout << d[t.fi][t.se] << '\n';
        while (t != s) {
//            cerr << t.fi << ' ' << t.se << ' ';
            ii pre = {t.fi - dx[trace[t.fi][t.se]], t.se - dy[trace[t.fi][t.se]]};
            if (d[t.fi][t.se] != d[pre.fi][pre.se])
            {
                int k = trace[t.fi][t.se];
//                cerr << k << '\n';
                if (k == 0) a[pre.fi][pre.se] = '<';
                if (k == 1) a[pre.fi][pre.se] = 'v';
                if (k == 2) a[pre.fi][pre.se] = '^';
                if (k == 3) a[pre.fi][pre.se] = '>';
            }
            t = pre;
        }
        For (i, 1, n) {
                For (j, 1, m) cout << a[i][j];
                cout << '\n';
        }
}

signed main(void) {
        ios_base::sync_with_stdio(false);cin.tie(nullptr);
        cout.tie(nullptr);

        #define task "a"
        if (fopen(task".inp", "r")) {
                freopen(task".inp", "r", stdin);
                freopen(task".out", "w", stdout);
        }//_______________________________
        Progess();
        cerr << "\nTime elapsed: " << (1.0 * clock() / CLOCKS_PER_SEC) << " s.\n";
        return (0 ^ 0);
}

Compilation message (stderr)

patkice.cpp: In function 'int main()':
patkice.cpp:126:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  126 |                 freopen(task".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
patkice.cpp:127:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  127 |                 freopen(task".out", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 30
• Subtask 2: 0 / 20