Submission #1293466

#	Time	Username	Problem	Language	Result	Execution time	Memory
1293466		trandaihao5555	Tracks in the Snow (BOI13_tracks)	C++20	100 / 100	425 ms	135108 KiB

tracks

#include <bits/stdc++.h>

#define int long long

#define debug     cout << "ok\n";
#define SQR(x)    (1LL * ((x) * (x)))
#define MASK(i)   (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
#define fi        first
#define se        second
#define pb        push_back

#define mp make_pair
#define pii pair<int,int>
#define pli pair<ll,int>
#define vi vector<int>

#define FAST ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef unsigned int ui;

using namespace std;

const int M = 1e9 + 7;
const int INF = 1e9 + 7;
const ll INFLL = (ll)2e18 + 7LL;
const ld PI = acos(-1);

const int dx[] = {1, -1, 0, 0, -1, 1, 1, -1};
const int dy[] = {0, 0, 1, -1, -1, -1, 1, 1};

template<class _, class __>
    bool minimize(_ &x, const __ y){
        if(x > y){
            x = y;
            return true;
        } else return false;
    }
template<class _, class __>
    bool maximize(_ &x, const __ y){
        if(x < y){
            x = y;
            return true;
        } else return false;
    }

template<class _,class __>
    void Add(_ &x, const __ y) {
        x += y;
        if (x >= M) {
            x -= M;
        }
        return;
    }

template<class _,class __>
    void Diff(_ &x, const __ y) {
        x -= y;
        if (x < 0) {
            x += M;
        }
        return;
    }

//--------------------------------------------------------------

const int MaxN = 5007;

int n,m,res = 0;
char a[MaxN][MaxN];
bool vis[MaxN][MaxN];

bool inSide(int x,int y) {
    return 1 <= x && x <= n && 1 <= y && y <= m;
}

void sol() {
    cin >> n >> m;
    for (int i=1;i<=n;i++) for (int j=1;j<=m;j++) {
        cin >> a[i][j];
    }
    char ch = 'x';
    deque<pii> q;
    q.push_back(mp(1,1));
    vis[1][1] = true;
    while (!q.empty()) {
        int x = q.front().fi;
        int y = q.front().se;
        if (a[x][y] != ch) res++;
        ch = a[x][y];
        q.pop_front();
        for (int i=0;i<4;i++) {
            int xx = x + dx[i];
            int yy = y + dy[i];
            if (!inSide(xx,yy) || vis[xx][yy] || a[xx][yy] == '.') continue;
            vis[xx][yy] = true;
            if (a[xx][yy] == a[x][y]) q.push_front(mp(xx,yy));
            else q.push_back(mp(xx,yy));
        }
    }
    cout << res;
}

signed main() {
//    freopen("test.inp","r",stdin);
//    freopen("test.out","w",stdout);
    FAST
    int t=1;
//    cin >> t;
    while (t--) sol();
}

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