#include <cstdio>
#define pinf 10000000

using namespace std;

int a[1001][1001] ;

char c ;

struct punct
{
    int x ;
    int y ;

};

punct coada[1000001],dragon[1000001] ;

int main()
{
    int i,j,n,m,w=0,p,u ;
    freopen("balaur.in","r",stdin) ;
    freopen("balaur.out","w",stdout) ;
    scanf("%d%d",&n,&m) ;
    c=getchar() ;
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            scanf("%c",&c) ;
            if(c=='.')
                a[i][j]=0 ;
            if(c=='*')
                a[i][j]=-1 ;
            if(c=='I')
                a[i][j]=pinf ;
            if(c=='D')
            {
                a[i][j]=1 ;
                w++ ;
                dragon[w].x=i ;
                dragon[w].y=j ;

            }
            c=getchar();
        }
    }


    p=u=1 ;

    /*for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
            printf("%d ",a[i][j]) ;
        printf("\n") ;
    }*/
    printf("%d",-1) ;

    return 0;
}