change default zeta_C compiler to gcc & complete 10815.c

zeta_C/completed/10815.c

@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int comp(const void *a, const void *b) {
+    return *(int *) a - *(int *) b;
+}
+
+int is_in(int x, int *cards, int size) {
+    int begin = 0, end = size - 1, mid;
+    while (begin <= end) {
+        mid = (begin + end) / 2;
+        if (cards[mid] == x) {
+            return 1;
+        } else if (cards[mid] > x) {
+            end = mid - 1;
+        } else {
+            begin = mid + 1;
+        }
+    }
+    return 0;
+}
+
+int main() {
+    int N;
+    scanf("%d", &N);
+
+    int cards[N];
+    for (int i = 0; i < N; i++) {
+        scanf("%d", &cards[i]);
+    }
+
+    qsort(cards, N, sizeof(int), comp);
+
+    int M;
+    scanf("%d", &M);
+
+    int check[M];
+    for (int i = 0; i < M; i++) {
+        scanf("%d", &check[i]);
+    }
+
+    for (int i = 0; i < M - 1; i++) {
+        printf("%d ", is_in(check[i], cards, N));
+    }
+    printf("%d\n", is_in(check[M - 1], cards, N));
+
+
+    return 0;
+}