Submission #464488

#	Time	Username	Problem	Language	Result	Execution time	Memory
464488		Aratab	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	633 ms	130928 KiB

tracks

/**
 * Author : Samuel Batara (Aratab)
**/ 
#include <bits/stdc++.h>
using namespace std;

int N,M;
string s[4001];
int dep[4001][4001];
vector<int> dx = {1,0,-1,0};
vector<int> dy = {0,1,0,-1};

bool inside(int x, int y) {
    return (x>-1 && x<N && y>-1 && y<M && s[x][y]!='.');
}

void dahiken() {
    cin >> N >> M;
    for(int i=0; i<N; i++) cin >> s[i];
    dep[0][0] = 1;
    deque<pair<int,int>> q;
    q.push_back({0,0});
    int ans = 1;
    while(!q.empty()) {
        int a,b; tie(a,b) = q.front(); q.pop_front();
        ans = max(ans, dep[a][b]);
        for(int i=0; i<4; i++) {
            int x = a + dx[i], y = b + dy[i];
            if(inside(x,y) && dep[x][y]==0) {
                if(s[a][b] == s[x][y]) {
                    dep[x][y] = dep[a][b];
                    q.push_front({x,y});
                } else {
                    dep[x][y] = dep[a][b] + 1;
                    q.push_back({x,y});
                }
            }
        }
    }
    cout << ans << '\n';
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    int ntc=1;
    //cin >> ntc;
    while(ntc--) {
        dahiken();
    }

    return 0;
}

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