Submission #636659

#	Time	Username	Problem	Language	Result	Execution time	Memory
636659		LKR__enjoyer	Tracks in the Snow (BOI13_tracks)	C++17	19.79 / 100	1401 ms	118968 KiB

tracks

#include<bits/stdc++.h>
#include <iostream>

using namespace std;
#define f first
#define s second
int n,m;
char grid[4000][4000];
int odl[4000][4000];
pair<int,int> ruchy[4]={{1,0},{-1,0},{0,1},{0,-1}};
void bfs(int i,int j)
{
deque<pair<int,int>> w; 
w.push_front({i,j});
    while(w.empty()==0)
    {
        pair<int,int> akt=w.front();
    w.pop_front();
        for(int z=0;z<4;z++)
        {
        int u1=akt.f+ruchy[z].f;
        int u2=akt.s+ruchy[z].s;    
            if(u1<0||u1>=n||u2<0||u2>=m||grid[u1][u2]=='.')continue;
        int waga=0;
            if(grid[akt.f][akt.s]!=grid[u1][u2])waga=1;
                if(odl[u1][u2]>odl[akt.f][akt.s]+waga)
                    {
                        odl[u1][u2]=odl[akt.f][akt.s]+waga;
                        if(waga==1)w.push_back({u1,u2});
                        else w.push_front({u1,u2});
                    }
        }
    }
}
int main()
{ ios_base::sync_with_stdio(); cin.tie();
  cin>>n>>m;
for(int i=0;i<n;i++)
{for(int j=0;j<m;j++)
{   if(i||j)odl[i][j]=1e9;
    cin>>grid[i][j];
}
}
bfs(0,0);
int wynik=-1;
for(int i=0;i<n;i++)
for(int j=0;j<m;j++)
wynik=max(wynik,odl[i][j]);    
cout<<wynik+1;
    return 0;
}

• Subtask 1: 6.666666666666667 / 30
• Subtask 2: 13.125 / 70