C++ :

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<queue>
#include<iostream>
using namespace std;
struct P
{
    int x,y;
    int time;
};
bool map[15][15][4];
char a[15][15];
bool vis[15][15][4];
int x[4]={1,0,-1,0};
int y[4]={0,1,0,-1};
int n,m;
int bfs(P s,P e)
{
    queue<P> q;
    q.push(s);
    vis[s.x][s.y][s.time]=1;
    bool flag=0;
    while(!q.empty())
    {
        P p=q.front();
        q.pop();
        //printf("%d-%d-%d\n",p.x,p.y,p.time);
        if(p.x==e.x&&p.y==e.y)
            return p.time;
        for(int i=0;i<4;i++)
        {
            int nx=p.x+x[i];
            int ny=p.y+y[i];
            if(nx>=0&&nx<n&&ny>=0&&ny<m&&!vis[nx][ny][(p.time+1)%4]&&!map[nx][ny][(p.time+1)%4])
            {
                vis[nx][ny][(p.time+1)%4]=1;
                P p1;
                p1.x=nx;p1.y=ny;p1.time=p.time+1;
                q.push(p1);
            }
        }
        int time=p.time+1;
        if(!map[p.x][p.y][(time)%4]&&!vis[p.x][p.y][(time)%4])
        {
            p.time++;
            q.push(p);
        }
    }
    return -1;
}
int main()
{
    //freopen("F input.txt","r",stdin);
    //freopen("F output.txt","w",stdout);
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        for(int i=0;i<n;i++)
            scanf("%s",a[i]);
        P s,e;
        memset(map,0,sizeof(map));
        memset(vis,0,sizeof(vis));
        for(int i=0;i<n;i++)
        {
            for(int j=0;j<m;j++)
            {
              if(a[i][j]=='S')
              {
                  s.x=i;
                  s.y=j;
                  s.time=0;
              }
              else if(a[i][j]=='E')
              {
                  e.x=i;
                  e.y=j;
              }
              else if(a[i][j]=='D')
              {
                  map[i][j][0]=1;
                  map[i-1][j][1]=1;
                  map[i-1][j+1][2]=1;
                  map[i][j+1][3]=1;
              }
            }
        }
        int k=0;
        k=bfs(s,e);
        if(k!=-1)
        printf("%d\n",k);
        else printf("kill the dog,god wen!\n");
    }
}