Submission #63731

#	Time	Username	Problem	Language	Result	Execution time	Memory
63731		Bodo171	Tracks in the Snow (BOI13_tracks)	C++14	46.77 / 100	2086 ms	146708 KiB

tracks

#include <iostream>
#include <fstream>
#include <queue>
using namespace std;
const int nmax=4005;
int d[nmax][nmax];
//pair<int,int> q[2][nmax*nmax];
string s[nmax];
int p[2],u[2];
bool E[nmax][nmax];
int use,mx,i,j,dd,n,m,li,ci,lf,cf,di;
int d1[]={-1,0,1,0};
int d2[]={0,-1,0,1};
void dij(int L,int C)
{

    deque< pair<int,int> > q;
    q.push_back({L,C});
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
           d[i][j]=n*m+1;
    d[L][C]=0;
        while(!q.empty())
        {
             li=q.front().first;ci=q.front().second;q.pop_front();
              for(di=0;di<4;di++)
              {
                  lf=li+d1[di];cf=ci+d2[di];
                  if(lf>=1&&cf>=1&&lf<=n&&cf<=m&&(s[lf][cf-1]=='R'||s[lf][cf-1]=='F'))
                  {
                      dd=d[li][ci]+(s[li][ci-1]!=s[lf][cf-1]);
                      if(dd<d[lf][cf])
                      {
                          d[lf][cf]=dd;
                          if(dd=d[li][ci]) q.push_front({lf,cf});
                          else q.push_back({lf,cf});
                      }
                  }
              }
        }
}
int main()
{
   // freopen("data.in","r",stdin);
    ios_base::sync_with_stdio(false);
    cin>>n>>m;getline(cin,s[0]);
    for(i=1;i<=n;i++)
    {
        getline(cin,s[i]);
    }
    dij(1,1);
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
          if(s[i][j-1]=='R'||s[i][j-1]=='F')
             mx=max(mx,d[i][j]);
    cout<<mx+1;
    return 0;
}

Compilation message (stderr)

tracks.cpp: In function 'void dij(int, int)':
tracks.cpp:35:32: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
                           if(dd=d[li][ci]) q.push_front({lf,cf});
                              ~~^~~~~~~~~~

• Subtask 1: 18.333333333333332 / 30
• Subtask 2: 28.4375 / 70