diff --git a/du4/program.c b/du4/program.c
index a20a671..e41301f 100644
--- a/du4/program.c
+++ b/du4/program.c
@@ -48,7 +48,7 @@ int main() {
                 default:
                     if (isdigit(symbol) || symbol == '.'){
                         if (operation == 0)
-                           strcat(number1, symbol+"");
+                            strcat(number1, symbol+"");
                         else if(!equals)
                             strcat(number2, symbol+"");
                         else