diff --git a/POJ/3069.cpp b/POJ/3069.cpp
new file mode 100644
index 0000000..f47642b
--- /dev/null
+++ b/POJ/3069.cpp
@@ -0,0 +1,96 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <vector>
+#include <algorithm>
+using namespace std;
+
+int R,N,cnt;
+vector<int> X;
+
+int find_target(int StartPoint,int range)
+{
+    if(StartPoint==N-1)
+    {
+        return N-1;
+    }
+    for(;StartPoint<N;StartPoint++)
+    {
+        if(X[StartPoint]<=range)
+        {
+            continue;
+        }
+        else
+        {
+            return StartPoint-1;
+        }
+    }
+    /// StartPoint==N
+    return N-1;
+}
+
+int find_next(int StartPoint,int Range)
+{
+    if(StartPoint==N-1)
+    {
+        return N;
+    }
+    for(;StartPoint<N;StartPoint++)
+    {
+        if(X[StartPoint]<=Range)
+        {
+            continue;
+        }
+        else
+        {
+            return StartPoint;
+        }
+    }
+    return N;
+
+}
+
+int main()
+{
+    while(scanf("%d %d",&R,&N)==2&&(N!=-1&&R!=-1))
+    {
+        X.clear();
+        for(int i=0; i<N; i++)
+        {
+            int tmp;
+            scanf("%d",&tmp);
+            X.push_back(tmp);
+        }
+        sort(X.begin(),X.end());
+        cnt=0;
+
+        int point=0;
+        while(point<N)
+        {
+            int range=X[point]+R;
+            int ans=find_target(point,range);
+            if(ans==point)
+            {
+                /// light this point : point
+                cnt++;
+                point=find_next(point,X[point]+R);
+                continue;
+            }
+            else if(ans==-1)
+            {
+                break;
+            }
+            else
+            {
+                /// light target point : ans
+                cnt++;
+                point=ans;
+            }
+            range=X[point]+R;
+            point=find_next(point,range);
+        }
+
+        printf("%d\n",cnt);
+    }
+    return 0;
+}