diff --git a/contrib/minizip/minizip.c b/contrib/minizip/minizip.c
index f458c85..61a9d4c 100644
--- a/contrib/minizip/minizip.c
+++ b/contrib/minizip/minizip.c
@@ -381,7 +381,7 @@ int main(int argc, char *argv[]) {
                   ((argv[i][1]=='o') || (argv[i][1]=='O') ||
                    (argv[i][1]=='a') || (argv[i][1]=='A') ||
                    (argv[i][1]=='p') || (argv[i][1]=='P') ||
-                   ((argv[i][1]>='0') || (argv[i][1]<='9'))) &&
+                   ((argv[i][1]>='0') && (argv[i][1]<='9'))) &&
                   (strlen(argv[i]) == 2)))
             {
                 FILE * fin;