Submission #651648

#	Time	Username	Problem	Language	Result	Execution time	Memory
651648		bojackduy	Tracks in the Snow (BOI13_tracks)	C++14	100 / 100	759 ms	130996 KiB

tracks

#include <iostream>
#include <queue>
#include <stack>
#include <algorithm>
#include <string.h>
#include <functional>
#define task ""
#define size() size() * 1ll 
#define all(x) (x).begin(), (x).end()
#define allr(x, sz) (x) + 1, (x) + 1 + sz
#define pb push_back
#define pii pair<int, int>
#define fi first
#define se second
#define MASK(x) (1LL << (x))
#define BIT(x,i) (((x) >> (i)) & 1)
#define numbit(x) __builtin_popcountll(x)

using namespace std;

const int N = 1e6 + 1;
const int M = 4e3 + 1;
const long long mod = 1e9 + 7;
const long long oo = 1e18 + 7;

typedef vector<int> vi;
typedef vector<pii> vii;
typedef long long ll;

template<class t>
bool mini(t &x,t y) {
    if (y < x) {
       x = y;
       return 1;
    }
return 0;
}
template<class t>
bool maxi(t &x,t y) {
    if (x < y) {
       x = y;
       return 1;
    }
return 0;
}
const int dx[] = {0, 0, 1, -1};
const int dy[] = {1, -1, 0, 0};
int n, m;
char a[M][M];
int d[M][M];
void solve(int test = -1) {
    cin >> n >> m;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            cin >> a[i][j];
        }
    }
    deque<pii> dq;
    dq.pb(pii(1, 1));
    d[1][1] = 1;
    int res = 0;
    while (dq.size()) {
        pii u = dq.front();
        dq.pop_front();
        maxi(res, d[u.fi][u.se]);
        for (int i = 0; i < 4; i++) {
            pii v = pii(u.fi + dx[i], u.se + dy[i]);
            if (v.fi < 1 || v.se < 1 || v.fi > n || v.se > m || a[v.fi][v.se] == '.' || d[v.fi][v.se] != 0) continue;
            if (a[u.fi][u.se] == a[v.fi][v.se]) {
                d[v.fi][v.se] = d[u.fi][u.se];
                dq.push_front(v);
            } else {
                d[v.fi][v.se] = d[u.fi][u.se] + 1;
                dq.pb(v);
            }
        }
    }
    cout << res;
}

int32_t main()  {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    // freopen(task".inp", "r", stdin);
    // freopen(task".out", "w", stdout);

    int T = 1;
    // cin >> T;
    for (int i = 1; i <= T; i++) {
        solve(i);
    }
return 0;
}
/*

*/

Compilation message (stderr)

tracks.cpp: In function 'void solve(int)':
tracks.cpp:8:23: warning: '*' in boolean context, suggest '&&' instead [-Wint-in-bool-context]
    8 | #define size() size() * 1ll
      |                       ^
tracks.cpp:62:15: note: in expansion of macro 'size'
   62 |     while (dq.size()) {
      |               ^~~~

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70