diff --git a/jlh/src/main/java/com/jlh/viewer/acm/HDU1004.java b/jlh/src/main/java/com/jlh/viewer/acm/HDU1004.java
new file mode 100644
index 0000000000000000000000000000000000000000..e9fe6057765309e05f92e9a74428d374009eee09
--- /dev/null
+++ b/jlh/src/main/java/com/jlh/viewer/acm/HDU1004.java
@@ -0,0 +1,57 @@
+package com.jlh.viewer.acm;
+
+import java.util.Scanner;
+
+/**
+ * com.jlh.viewer.acm
+ * Created by ASUS on 2017/3/14.
+ * 19:43
+ */
+public class HDU1004 {
+    private static String index[]=new String[1005];
+    private static int length;
+    private static int count[]=new int[1005];
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        while (true){
+            int n= sc.nextInt();
+            if (n==0)
+                break;
+            sc.nextLine();
+            init(n);
+            for (int i=0;i<n;i++){
+                String color = sc.nextLine();
+                int j= isIndex(color);
+                if (j==-1){
+                    index[length]=color;
+                    j=length++;
+                }
+                count[j]++;
+            }
+            int max=-1,maxIndex=-1;
+            for (int i=0;i<length;i++){
+                if (max<count[i]){
+                    max=count[i];
+                    maxIndex=i;
+                }
+            }
+            System.out.println(index[maxIndex]);
+        }
+    }
+
+    public static void  init(int n){
+        for (int i=0;i<=n;i++){
+            index[i]="";
+            count[i]=0;
+        }
+        length=0;
+    }
+
+    public static int isIndex(String color){
+        for (int i=0;i<length;i++){
+            if (color.equals(index[i]))
+                return i;
+        }
+        return -1;
+    }
+}
diff --git a/jlh/src/main/java/com/jlh/viewer/acm/HDU1005.java b/jlh/src/main/java/com/jlh/viewer/acm/HDU1005.java
new file mode 100644
index 0000000000000000000000000000000000000000..42a638ffaf0c48140365d44944887dbd3c953133
--- /dev/null
+++ b/jlh/src/main/java/com/jlh/viewer/acm/HDU1005.java
@@ -0,0 +1,29 @@
+package com.jlh.viewer.acm;
+
+import java.util.Scanner;
+
+/**
+ * com.jlh.viewer.acm
+ * Created by ASUS on 2017/3/14.
+ * 20:28
+ */
+public class HDU1005 {
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        while (true){
+            int a=sc.nextInt(),b=sc.nextInt(),c=sc.nextInt(),i;
+            if (a==0&&b==0&&c==0)
+                break;
+            int arr[]=new int[105];
+            arr[1]=1;
+            arr[2]=1;
+            for (i=3;i<100;i++){
+                arr[i]=(a*arr[i-1]+b*arr[i-2])%7;
+                if(arr[i] == 1 && arr[i-1] == 1)
+                    break;
+            }
+            arr[0]=arr[i-2];
+            System.out.println(arr[c%(i-2)]);
+        }
+    }
+}
diff --git a/jlh/src/main/java/com/jlh/viewer/algorithm/MergeSort.java b/jlh/src/main/java/com/jlh/viewer/algorithm/MergeSort.java
new file mode 100644
index 0000000000000000000000000000000000000000..89d6177e46ce95ada404dd000e1bd0d661cf12c9
--- /dev/null
+++ b/jlh/src/main/java/com/jlh/viewer/algorithm/MergeSort.java
@@ -0,0 +1,67 @@
+package com.jlh.viewer.algorithm;
+
+import java.util.Arrays;
+
+/**
+ * Created by jlh
+ * On 2017/3/14 0014.
+ */
+public class MergeSort {
+    public static void main(String[] args) {
+        int b[]={4,5,1,2,3,8,11,6,7,10};
+        MergeSort mergeSort= new MergeSort();
+        mergeSort.sort(b,0,b.length);
+        Arrays.stream(b).forEach(System.out::println);
+    }
+
+    public void sort (int a[],int first,int last){
+        reslove(a,first,last-1,new int[a.length]);
+    }
+
+    public void reslove(int a[],int first,int last,int []temp){
+        if (first<last){
+            int mid = (first+last)/2;
+            //以后处理边界问题，统一从0到length-1 然后用包涵等于处理，0到length 不包含等于处理的时候逻辑很容易混乱
+            reslove(a,first,mid,temp);
+            reslove(a,mid+1,last,temp);
+            merge(a,first,mid,last,temp);
+        }
+    }
+
+    public void merge (int a[],int first,int mid,int last,int []temp){
+        int i=first,j=mid+1,k=0;
+        while (i<=mid&&j<=last){
+            if (a[i]<=a[j])
+                temp[k++]=a[i++];
+            else
+                temp[k++]=a[j++];
+        }
+        while (i <= mid)
+            temp[k++] = a[i++];
+
+        while (j <= last)
+            temp[k++] = a[j++];
+        for (i=0;i<k;i++){
+            a[first+i]=temp[i];
+        }
+    }
+
+    public int[] mergeArr (int a[],int b[]){
+        int i=0,j=0,k=0;
+        int result [] = new int[a.length+b.length];
+        while (i < a.length && j < b.length)
+        {
+            if (a[i] < b[j])
+                result[k++] = a[i++];
+            else
+                result[k++] = b[j++];
+        }
+
+        while (i < a.length)
+            result[k++] = a[i++];
+
+        while (j < b.length)
+            result[k++] = b[j++];
+        return result;
+    }
+}