Submission #1322359

#	Time	Username	Problem	Language	Result	Execution time	Memory
1322359		alexandros	Tracks in the Snow (BOI13_tracks)	C++20	100 / 100	1108 ms	269680 KiB

tracks

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

vector<vector<int>> vec;
deque<pair<ll, ll>> dq;
vector<vector<ll>> dist;

int main() 
{
    ll width, height;
    char cur;
    scanf("%lld %lld", &height, &width);
    vec.assign(height, vector<int>(width, 0));
    for(ll i = 0; i < height; i++)
    {
        for(ll j = 0; j < width; j++)
        {
            scanf(" %c", &cur);
            if(cur == 'R')
            {
                vec[i][j] = 1;
            }
            else if(cur == 'F')
            {
                vec[i][j] = 2;
            }
        }
    }
    dist.assign(height, vector<ll>(width, -1));
    dq.push_back({0, 0});
    dist[0][0] = 1;
    pair<ll, ll> tp;
    ll big = 1;
    while(!dq.empty())
    {
        tp = dq.front();
        dq.pop_front();
        for(ll i = -1; i <= 1; i++)
        {
            for(ll j = -1; j <= 1; j++)
            {
                if(i != 0 && j != 0) continue;
                if(i == 0 && j == 0) continue;
                ll ni = tp.first + i;
                ll nj = tp.second + j;
                if(ni < 0 || nj < 0) continue;
                if(ni >= height || nj >= width) continue;
                if(dist[ni][nj] != -1) continue;
                if(vec[ni][nj] == 0) continue;
                dist[ni][nj] = dist[tp.first][tp.second];
                if(vec[ni][nj] == vec[tp.first][tp.second]) dq.push_front({ni, nj});
                else
                {
                    dq.push_back({ni, nj});
                    dist[ni][nj]++;
                }
                big = max(big, dist[ni][nj]);
            }
        }
    }
    printf("%lld", big);
}

Compilation message (stderr)

tracks.cpp: In function 'int main()':
tracks.cpp:15:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     scanf("%lld %lld", &height, &width);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:21:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |             scanf(" %c", &cur);
      |             ~~~~~^~~~~~~~~~~~~

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