Submission #492134

#	Time	Username	Problem	Language	Result	Execution time	Memory
492134		ToroTN	Tracks in the Snow (BOI13_tracks)	C++14	31.25 / 100	487 ms	78648 KiB

tracks

#include<bits/stdc++.h>
using namespace std;
int n,m,dx[]={1,-1,0,0},dy[]={0,0,1,-1},d[4005][4005],u,v,sx,sy,x,y;
char s[4005][4005];
queue<pair<int,int> > q;
int main()
{
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++)
    {
        scanf("%s",s[i]+1);
    }
    sx=1;
    sy=1;
    for(int i=1;;i++)
    {
        //printf("%d\n",i);
        q.push({sx,sy});
        d[sx][sy]=1;
        sx=-1;
        sy=-1;
        while(!q.empty())
        {
            u=q.front().first;
            v=q.front().second;
            ///printf("%d %d %d\n",u,v,d[u][v]);
            q.pop();
            for(int j=0;j<4;j++)
            {
                x=u+dx[j];
                y=v+dy[j];
                if(x>=1&&x<=n&&y>=1&&y<=m)
                {
                    if(s[x][y]!='.')
                    {
                        if(s[x][y]!=s[u][v])
                        {
                            if(d[x][y]==0)
                            {
                                sx=x;
                                sy=y;
                            }
                        }else
                        {
                            //printf("%d %d %d %d\n",u,v,x,y);
                            if(d[x][y]==0)
                            {
                                //printf("%d %d %d\n",x,y,d[x][y]);
                                d[x][y]=1;
                                q.push({x,y});
                            }
                        }
                    }
                }
            }
        }
        if(sx==-1&&sy==-1)
        {
            printf("%d\n",i);
            break;
        }
    }
}

Compilation message (stderr)

tracks.cpp: In function 'int main()':
tracks.cpp:8:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
tracks.cpp:11:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 |         scanf("%s",s[i]+1);
      |         ~~~~~^~~~~~~~~~~~~

• Subtask 1: 5 / 30
• Subtask 2: 26.25 / 70