[Week01] BOJ_1920: 수 찾기

Author: sukangpunch

weekly/week01/BOJ_1920_수 찾기/sukangpunch.java

@@ -0,0 +1,53 @@
+package stduy.week01;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+
+public class BOJ_1920 {
+
+    static int [] A;
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringBuilder sb = new StringBuilder();
+
+        int N = Integer.parseInt(br.readLine());
+        String [] s = br.readLine().split(" ");
+        A = new int[N];
+        for(int i=0;i<N;i++){
+            A[i] = Integer.parseInt(s[i]);
+        }
+        Arrays.sort(A);
+
+        int M = Integer.parseInt(br.readLine());
+        s = br.readLine().split(" ");
+
+        for(int i=0;i<M;i++){
+            int num = Integer.parseInt(s[i]);
+            int result = findNumByBinarySearch(0, N - 1, num);
+            sb.append(result).append("\n");
+        }
+
+        System.out.println(sb);
+
+    }
+
+    private static int findNumByBinarySearch(int start, int end, int target) {
+        if(start > end){
+            return 0;
+        }
+
+        int mid = (start + end) / 2;
+
+        if(A[mid] == target){
+            return 1;
+        }else if(A[mid] > target){
+            return findNumByBinarySearch(start, mid - 1, target);
+        }else{
+            return findNumByBinarySearch(mid + 1, end, target);
+        }
+    }
+
+}