BOJ1920_수찾기 java solution

mong3125/이분탐색/BOJ1920_수찾기.java

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+package 이진탐색;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.StringTokenizer;
+
+public class BOJ1920_수찾기 {
+
+    static int[] A;
+    static int[] targets;
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        A = new int[N];
+
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < A.length; i++) {
+            A[i] = Integer.parseInt(st.nextToken());
+        }
+
+        int M = Integer.parseInt(br.readLine());
+        targets = new int[M];
+        st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < targets.length; i++) {
+            targets[i] = Integer.parseInt(st.nextToken());
+        }
+
+        Arrays.sort(A);
+
+        for (int i = 0; i < targets.length; i++) {
+            int now = targets[i];
+            System.out.println(binary(0, A.length - 1, now) ? 1 : 0);
+        }
+    }
+
+    public static boolean binary(int from, int to, int n) {
+        if (from > to) return false;
+        int mid = (from + to) / 2;
+
+        if (A[mid] == n) return true;
+        else if (A[mid] > n) return binary(from, mid - 1, n);
+        else return binary(mid + 1, to, n);
+    }
+}