init commit

3sem/cnts/contest14/05.c

@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <signal.h>
+
+volatile int last_prime = 0;
+volatile int cnt = 0;
+
+void
+f(int n)
+{
+    if (++cnt == 4) {
+        exit(0);
+    }
+
+    printf("%d\n", last_prime);
+    fflush(stdout);
+
+    return;
+}
+
+void
+exit_term(int n)
+{
+    exit(0);
+
+    return;
+}
+
+int
+is_prime(int n)
+{
+    if (n < 2) {
+        return 0;
+    }
+
+    for (int i = 2; i * i <= n; ++i) {
+        if (n % i == 0) {
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+int
+main(int argc, char *argv[])
+{
+    sigaction(SIGINT, &(struct sigaction){.sa_handler = f, .sa_flags = SA_RESTART}, NULL);
+    sigaction(SIGTERM, &(struct sigaction){.sa_handler = exit_term, .sa_flags = SA_RESTART}, NULL);
+
+    printf("%d\n", getpid());
+    fflush(stdout);
+
+    int a, b;
+    scanf("%d", &a);
+    scanf("%d", &b);
+
+    a = (a < 2) ? 2 : a;
+
+    for (int i = a; i < b; ++i) {
+        if (is_prime(i)) {
+            last_prime = i;
+        }
+    }
+
+    printf("-1\n");
+    fflush(stdout);
+
+    return 0;
+}