diff --git a/casm/c.c b/casm/c.c
index b74424d..02c4a95 100644
--- a/casm/c.c
+++ b/casm/c.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 
 int sum(int a, int b) {
     return a+b;
@@ -6,10 +7,16 @@ int sum(int a, int b) {
 
 void print(int num) {
     printf("%d\n", num);
+    fflush(stdout);
 }
 
 int scan() {
+    char buffer[100];
     int res;
-    scanf("%d", &res);
-    return res;
+    if (fgets(buffer, sizeof(buffer), stdin) != NULL) {
+        if (sscanf(buffer, "%d", &res) == 1) {
+            return res;
+        }
+    }
+    return 0; // or handle error
 }
\ No newline at end of file