diff --git a/HDOJ/5881_chen9510.cpp b/HDOJ/5881_chen9510.cpp
new file mode 100644
index 0000000..6e0f6ef
--- /dev/null
+++ b/HDOJ/5881_chen9510.cpp
@@ -0,0 +1,37 @@
+#include <iostream>
+#include <algorithm>
+#include <stdio.h>
+#include <queue>
+#include <cmath>
+#include <string.h>
+using namespace std;
+
+int main()
+{
+    long long L,R;
+    while(scanf("%lld%lld",&L,&R)!=EOF)
+    {
+        if(L==R)
+        {
+            if(R<=1) puts("0");
+            else if(R==2) puts("1");
+            else puts("2");
+            continue;
+        }
+        if(L==0)
+        {
+            if(R==1) puts("0");
+            else if(R==2) puts("1");
+            else printf("%lld\n",(R+1)/2);
+        }
+        else
+        {
+            if(L==1&&R==2)  puts("1");
+            else{
+            if(L+2>=R-1) puts("2");
+            else printf("%lld\n",(R-L+2)/2);
+            }
+        }
+    }
+    return 0;
+}