diff --git "a/4\354\243\274\354\260\250/42586/42586_\352\266\214\355\214\220\354\244\200.java" "b/4\354\243\274\354\260\250/42586/42586_\352\266\214\355\214\220\354\244\200.java"
new file mode 100644
index 0000000..48fb78e
--- /dev/null
+++ "b/4\354\243\274\354\260\250/42586/42586_\352\266\214\355\214\220\354\244\200.java"
@@ -0,0 +1,24 @@
+public class No_42586 {
+    public int[] solution(int[] progresses, int[] speeds) {
+        List<Integer> answer = new ArrayList<>();
+
+        int deploy = (int) Math.ceil((double) (100 - progresses[0]) / speeds[0]);
+        int cnt = 1;
+        for (int i = 1; i < progresses.length; i++) {
+            int day = (int) Math.ceil((double) (100 - progresses[i]) / speeds[i]);
+            if (deploy < day) {
+                answer.add(cnt);
+                deploy = day;
+                cnt = 1;
+
+            } else {
+                cnt++;
+            }
+            if (i == progresses.length - 1) {
+                answer.add(cnt);
+            }
+        }
+
+        return answer.stream().mapToInt(Integer::intValue).toArray();
+    }
+}
\ No newline at end of file
diff --git "a/4\354\243\274\354\260\250/42885/42585_\352\266\214\355\214\220\354\244\200.java" "b/4\354\243\274\354\260\250/42885/42585_\352\266\214\355\214\220\354\244\200.java"
new file mode 100644
index 0000000..f1bd876
--- /dev/null
+++ "b/4\354\243\274\354\260\250/42885/42585_\352\266\214\355\214\220\354\244\200.java"
@@ -0,0 +1,25 @@
+public class No_42885 {
+    public static void main(String[] args) {
+        int[] ints = {70, 50, 80, 50};
+        int[] ints2 = {70, 50, 80};
+        System.out.println(new No_42885().solution(ints, 100));
+    }
+
+    public int solution(int[] people, int limit) {
+        int answer = 0;
+
+        Arrays.sort(people);
+        int j = 0;
+        for (int i = people.length - 1; i >= 0; i--) {
+            if (i < j) {
+                break;
+            }
+
+            if (people[i] + people[j] <= limit) {
+                j++;
+            }
+            answer++;
+        }
+        return answer;
+    }
+}
\ No newline at end of file
diff --git "a/4\354\243\274\354\260\250/43165/43165_\352\266\214\355\214\220\354\244\200.java" "b/4\354\243\274\354\260\250/43165/43165_\352\266\214\355\214\220\354\244\200.java"
new file mode 100644
index 0000000..d4d14b9
--- /dev/null
+++ "b/4\354\243\274\354\260\250/43165/43165_\352\266\214\355\214\220\354\244\200.java"
@@ -0,0 +1,18 @@
+public class No_43165 {
+    // https://travelerfootprint.tistory.com/365
+    static int answer = 0;
+    public int solution(int[] numbers, int target) {
+        DFS(numbers, target, 0, 0);
+        return answer;
+    }
+
+    public static void DFS(int[] numbers, int target, int sum, int deep) {
+        if (deep == numbers.length) {
+            if (sum == target) answer++;
+            return;
+        }
+
+        DFS(numbers, target, sum + numbers[deep], deep + 1);
+        DFS(numbers, target, sum - numbers[deep], deep + 1);
+    }
+}
\ No newline at end of file
diff --git "a/4\354\243\274\354\260\250/64065/64065_\352\266\214\355\214\220\354\244\200.java" "b/4\354\243\274\354\260\250/64065/64065_\352\266\214\355\214\220\354\244\200.java"
new file mode 100644
index 0000000..befe13f
--- /dev/null
+++ "b/4\354\243\274\354\260\250/64065/64065_\352\266\214\355\214\220\354\244\200.java"
@@ -0,0 +1,21 @@
+public class No_64065 {
+    public int[] solution(String s) {
+        int[] answer = {};
+
+        s = s.substring(2, s.length() - 2);
+        String[] splitS = s.split("},\\{");
+        Arrays.sort(splitS, (str1, str2) -> Integer.compare(str1.length(), str2.length()));
+        List<Integer> list = new ArrayList<>();
+        for (String str : splitS) {
+            String[] splitStr = str.split(",");
+            for (String s1 : splitStr) {
+                int i = Integer.parseInt(s1);
+                if (!list.contains(i)) {
+                    list.add(i);
+                }
+            }
+        }
+
+        return list.stream().mapToInt(Integer::intValue).toArray();
+    }
+}
\ No newline at end of file