diff --git a/src/BaekJoon/Dltmd202/10773/Main.java b/src/BaekJoon/Dltmd202/10773/Main.java
new file mode 100644
index 0000000..4bc8de8
--- /dev/null
+++ b/src/BaekJoon/Dltmd202/10773/Main.java
@@ -0,0 +1,30 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Stack;
+
+/**
+ * 제로
+ * https://www.acmicpc.net/problem/10773
+ */
+public class Main {
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static StringBuilder sb = new StringBuilder();
+
+    public static void main(String[] args) throws IOException {
+        int k = Integer.parseInt(br.readLine());
+        Stack<Integer> stack = new Stack<>();
+
+        for (int i = 0; i < k; i++) {
+            int data = Integer.parseInt(br.readLine());
+
+            if(data == 0) stack.pop();
+            else stack.push(data);
+        }
+
+        System.out.println(
+                stack.stream()
+                        .mapToInt(Integer::intValue).sum()
+        );
+    }
+}
diff --git a/src/BaekJoon/Dltmd202/10814/Main.java b/src/BaekJoon/Dltmd202/10814/Main.java
new file mode 100644
index 0000000..b431c4d
--- /dev/null
+++ b/src/BaekJoon/Dltmd202/10814/Main.java
@@ -0,0 +1,68 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.StringTokenizer;
+
+/**
+ * 나이순 정렬
+ * https://www.acmicpc.net/problem/10814
+ */
+public class Main {
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static StringBuilder sb = new StringBuilder();
+
+    public static void main(String[] args) throws IOException {
+        int n = Integer.parseInt(br.readLine());
+        Person[] people = new Person[n];
+
+        for (int i = 0; i < n; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            people[i] = new Person(
+                    Integer.parseInt(st.nextToken()),
+                    st.nextToken()
+            );
+        }
+
+        Arrays.stream(people)
+                .sorted(
+                        Comparator.comparingInt(Person::getAge)
+                                .thenComparing(
+                                        Comparator.comparingInt(Person::getId))
+                )
+                .forEach(sb::append);
+
+        System.out.println(sb.toString().trim());
+    }
+
+    static class Person{
+        static int seq = 0;
+        int id;
+        int age;
+        String name;
+
+        public Person(int age, String name) {
+            this.id = seq++;
+            this.age = age;
+            this.name = name;
+        }
+
+        public int getAge(){
+            return age;
+        }
+
+        public String getName(){
+            return name;
+        }
+
+        public int getId(){
+            return id;
+        }
+
+        @Override
+        public String toString() {
+            return age + " " + name + "\n";
+        }
+    }
+}
diff --git a/src/BaekJoon/Dltmd202/10816/Main.java b/src/BaekJoon/Dltmd202/10816/Main.java
new file mode 100644
index 0000000..16e944d
--- /dev/null
+++ b/src/BaekJoon/Dltmd202/10816/Main.java
@@ -0,0 +1,46 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.StringTokenizer;
+
+/**
+ * 숫자 카드 2
+ * https://www.acmicpc.net/problem/10816
+ */
+public class Main {
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static StringBuilder sb = new StringBuilder();
+
+    public static void main(String[] args) throws IOException {
+        int n = Integer.parseInt(br.readLine());
+
+        Map<Integer, Integer> map = new HashMap<>();
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < n; i++) {
+            int data = Integer.parseInt(st.nextToken());
+            if(!map.containsKey(data)){
+                map.put(data, 1);
+            } else {
+                map.put(data, map.get(data) + 1);
+            }
+        }
+
+        int m = Integer.parseInt(br.readLine());
+
+        st = new StringTokenizer(br.readLine());
+
+        for (int i = 0; i < m; i++) {
+            int data = Integer.parseInt(st.nextToken());
+            if(!map.containsKey(data))
+                sb.append(0)
+                        .append(" ");
+            else {
+                sb.append(map.get(data))
+                        .append(" ");
+            }
+        }
+        System.out.println(sb.toString());
+    }
+}
diff --git a/src/BaekJoon/Dltmd202/10828/Main.java b/src/BaekJoon/Dltmd202/10828/Main.java
new file mode 100644
index 0000000..65e1aa3
--- /dev/null
+++ b/src/BaekJoon/Dltmd202/10828/Main.java
@@ -0,0 +1,37 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Stack;
+
+/**
+ * 스택
+ * https://www.acmicpc.net/problem/10828
+ */
+public class Main {
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static StringBuilder sb = new StringBuilder();
+
+    public static void main(String[] args) throws IOException {
+        int n = Integer.parseInt(br.readLine());
+        Stack<Integer> stack = new Stack<>();
+        for (int i = 0; i < n; i++) {
+            String command = br.readLine();
+            if (command.startsWith("push")){
+                int data = Integer.parseInt(command.substring(5));
+                stack.push(data);
+            } else {
+                if (command.equals("top")) {
+                    sb.append(!stack.isEmpty() ? stack.peek() : -1);
+                } else if (command.equals("pop")){
+                    sb.append(!stack.isEmpty() ? stack.pop() : -1);
+                } else if(command.equals("size")){
+                    sb.append(stack.size());
+                } else if(command.equals("empty")){
+                    sb.append(stack.isEmpty() ? 1: 0);
+                }
+                sb.append("\n");
+            }
+        }
+        System.out.println(sb.toString());
+    }
+}