delete pics to save space

2.11624.cpp

@@ -0,0 +1,80 @@
+#include<cstdio>
+#include<cstring>
+#include<queue>
+using namespace std;
+#define For(i,a,b) for(int i=a;i<=b;++i)
+const int maxn=1005;
+const int oo=0x3f3f3f3f;
+struct Node
+{
+	int r,c,t;
+	Node(int R,int C,int T):r(R),c(C),t(T) { }
+};
+queue<Node> Q;
+int T,n,m,p[maxn][maxn],vis[maxn][maxn],sr,sc;
+int dr[]={0,0,1,-1};
+int dc[]={1,-1,0,0};
+char mp[maxn][maxn];
+void init()
+{
+	while(Q.size())
+	{
+		Node u=Q.front();Q.pop();
+		For(i,0,3)
+		{
+			int vr=u.r+dr[i],vc=u.c+dc[i];
+			if((vr>=1&&vr<=n&&vc>=1&&vc<=m)&&mp[vr][vc]!='#'&&p[vr][vc]==oo)
+			{
+				Q.push(Node(vr,vc,0));
+				p[vr][vc]=p[u.r][u.c]+1;
+			}
+		}
+	}
+}
+void bfs()
+{
+	while(Q.size()) Q.pop();
+	Q.push(Node(sr,sc,0));
+	vis[sr][sc]=1;
+	while(Q.size())
+	{
+		Node u=Q.front();Q.pop();
+		if(u.r==n||u.r==1||u.c==1||u.c==m) { printf("%d\n",u.t+1); return; }
+		For(i,0,3)
+		{
+			int vr=u.r+dr[i],vc=u.c+dc[i];
+			if((vr>=1&&vr<=n&&vc>=1&&vc<=m)&&mp[vr][vc]!='#'&&!vis[vr][vc]&&(u.t+1<p[vr][vc]))
+			{
+				Q.push(Node(vr,vc,u.t+1));
+				vis[vr][vc]=1;
+			}
+		}
+	}
+	puts("IMPOSSIBLE");
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d",&T);
+	while(T-->0)
+	{
+		while(Q.size()) Q.pop();
+		memset(vis,0,sizeof(vis));
+		memset(p,oo,sizeof(p));
+		scanf("%d%d",&n,&m);
+		For(i,1,n) scanf("%s",mp[i]+1);
+		For(i,1,n) For(j,1,m)
+		{
+			if(mp[i][j]=='F')
+			{
+				Q.push(Node(i,j,0));
+				p[i][j]=0;
+			}
+			if(mp[i][j]=='J') sr=i,sc=j;
+		}
+		init(); bfs();
+	}
+	return 0;
+}