Codeforces Round #224 (Div. 2) D. Ksenia and Pawns(二)
f(t==best) { cnt++; nx[cnt]=i,ny[cnt]=j; } if(best>=INF) { ans=-1; return ; } } } } if(best==-1) { ans=0; return ; } memset(vis,0,sizeof(vis)); k=0; dfs1(nx[1],ny[1]); flag=0; k=1; for(i=2;i<=cnt;i++) { dfs1(nx[i],ny[i]); if(flag) break ; } ans=2*best-1+flag; } int main() { int i,j,t; while(~scanf("%d%d",&n,&m)) { for(i=1; i<=n; i++) { scanf("%s",mp[i]+1); } solve(); printf("%d\n",ans); } return 0; }