Cod sursa(job #134454)
#include <fstream.h>
#include <string.h>
#define MAX 1015
ifstream fin ("barbar.in");
ofstream fout ("barbar.out");
const int x[4]={-1,0,0,1};
const int y[4]={0,-1,1,0};
int a[20][20],n,m,xi,xf,yf,yi,xx[MAX],yy[MAX],numar,ok=0;
void citire()
{
char s[1010];
fin>>n>>m;
fin.getline(s,100);
for (int i=1;i<=n;i++)
{
fin.getline(s,1010);
for (int j=0;j<=m;j++)
if (s[j]=='*')
a[i][j+1]=-1;
else
if (s[j]=='D')
{
xx[numar]=i;
yy[numar]=j+1;
numar++;
}
else
if (s[j]=='I')
{
xi=i;
yi=j+1;
}
else
if (s[j]=='O')
{
xf=i;
yf=j+1;
}
}
}
int min (int a,int b)
{
if (a<b)
return a;
return b;
}
void lee (int q,int w)
{
int ii[MAX*MAX], jj[MAX*MAX],nr=1;
ii[0]=q;
jj[0]=w;
a[q][w]=1;
for (int i=0;i<nr;i++)
for (int k=0;k<4;k++)
if (a[ii[i] +x[k]][jj[i] +y[k]]!=-1)
if (ok==1){
a[ii[i] +x[k]][jj[i] +y[k]]=min(a[ii[i] +x[k]][jj[i] +y[k]],a[ii[i]][jj[i]]+1);
ii[nr]=ii[i]+x[k];
jj[nr]=jj[i]+y[k];
nr++;
}
else
if (a[ii[i] +x[k]] [jj[i] +y[k]]==0)
{
a[ii[i] +x[k]][jj[i] +y[k]] = a[ii[i]][jj[i]]+1;
ii[nr]=ii[i]+x[k];
jj[nr]=jj[i]+y[k];
nr++;
}
}
void fct()
{
int max=n;
if (m>n)
max=m;
for (int r=0;r<=max;r++)
{
a[r][0]=-1;
a[r][m+1]=-1;
a[n+1][r]=-1;
a[0][r]=-1;
}
lee(xx[0],yy[0]);
ok=1;
for (int i=1;i<numar;i++)
lee(xx[i],yy[i]);
}
void caut()
{
int xx[MAX*MAX*2],yy[MAX*MAX*2],nr=1;
xx[0]=xi;
yy[0]=yi;
for (int i=0;i<nr;i++)
for (int k=0;k<4;k++)
if (a[xx[i] +x[k]][yy[i] +y[k]]!=-1)
{
a[xx[i] +x[k]][yy[i] +y[k]]=min(a[xx[i]+x[k]] [yy[i]+y[k]],a[xx[i] ][yy[i]]);
xx[nr]=xx[i]+x[k];
yy[nr]=yy[i]+y[k];
nr++;
}
}
int main ()
{
citire();
fct();
caut();
return 0;
}