diff --git a/st.c b/st.c
index df660ff..fbbdc34 100644
--- a/st.c
+++ b/st.c
@@ -68,7 +68,7 @@ char *argv0;
 #define SERRNO strerror(errno)
 #define MIN(a, b)  ((a) < (b) ? (a) : (b))
 #define MAX(a, b)  ((a) < (b) ? (b) : (a))
-#define LEN(a)     (sizeof(a) / sizeof(a[0]))
+#define LEN(a)     (sizeof(a) / sizeof(a)[0])
 #define DEFAULT(a, b)     (a) = (a) ? (a) : (b)
 #define BETWEEN(x, a, b)  ((a) <= (x) && (x) <= (b))
 #define LIMIT(x, a, b)    (x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x)