diff --git a/README b/README
index 604a978..8d8ef7f 100644
--- a/README
+++ b/README
@@ -4,15 +4,9 @@ kecerahan
 kontrol kecerahan layar dengan cli
 
 #instalasi
-sebelum memulai, pastikan 'tcc' sudah tersedia sebagai compiler-nya,
-jika belum silahkan instal terlebih dahulu di https://bellard.org/tcc/
-atau instal melalui package manager yang sudah tersedia di OS anda.
-=======
-=========
-#pemasangan
-edit terlebih dahulu file main.c dan ganti DEVICES pada line 3:
+silahkan clone terlebih dahulu 'git clone git://github.com/owodev/kecerahan.git'
 
-kemudian, edit terlebih dahulu file kecerahan.c dan ganti DEVICES pada line 3:
+kemudian, edit file main.c dan ganti DEVICES pada baris 3:
 # define TARGET "/sys/class/backlight/DEVICES/brightness"
 
 lalu ketik:
diff --git a/main.c b/main.c
index 2dbbe6b..1f9304f 100644
--- a/main.c
+++ b/main.c
@@ -1,65 +1,24 @@
 #include <stdio.h>
+#include <stdlib.h>
+
+#define ERROR(...) do { fprintf(stderr, __VA_ARGS__); return 2; } while(0)
+
 /* silahkan edit 'DEVICES' dan sesuaikan dengan devices yang kalian punya */
 #define TARGET "/sys/class/backlight/DEVICES/brightness"
 
-int char_toint(char *arr) {
-        int num = 0;
-        short digit, mult = 1, offset = 0;
-        if (*arr == '-') {
-                mult = -1;
-                offset++;
-        } else if (*arr == '+') {
-                offset++;
-        }
-        while (*(arr + offset) != '\0') {
-                digit = * (arr + offset) - 48;
-                num = num * 10 + digit;
-                offset++;
-        }
-        return num * mult;
-}
+int main(int argc, char **argv) {
 
-void int_tochar(int num, char *buf) {
-        short digit, offset = 0;
-        int save = num, div = 1;
-        while (save > 0) {
-                div *= 10;
-                save /= 10;
-        }
-        div /= 10;
+    if(argc != 2)
+        ERROR("[%s] untuk cara penggunaan silaskan baca manpage 'man %s'\n", argv[0], argv[0]);
 
-        while (div >= 1) {
-                digit = num / div % 10;
-                div /= 10;
-                *(buf + offset) = digit + 48;
-                offset++;
-        }
-        *(buf + offset) = '\0';
-}
+    FILE *device_file;
+    device_file = fopen(TARGET, "w");
+
+    if(device_file == NULL)
+        ERROR("[%s] silahkan edit DEVICES di main.c! dan jalankan sebagai root!\n", argv[0]);
+        
+    fprintf(device_file, "%s", argv[1]);
+    fclose(device_file);
 
-int main(int argc, char *argv[]) {
-        if (argc == 2) {
-                FILE *korban;
-                if (argv[1][0] != '-' && argv[1][0] != '+') {
-                        korban = fopen(TARGET, "w");
-                        fprintf(korban, "%s", argv[1]);
-                        fclose(korban);
-                } else {
-                        char buff[4];
-                        korban = fopen(TARGET, "r");
-                        fscanf(korban, "%s", buff);
-                        fclose(korban);
-                        int d = char_toint(buff);
-                        int step = char_toint(argv[1]);
-                        d += step;
-                        int_tochar(d, buff);
-                        korban = fopen(TARGET, "w");
-                        fprintf(korban, "%s", buff);
-                        fclose(korban);
-                }
-                return 0;
-        } else {
-                printf("please input a valid number and run as root \n");
-                return 0;
-        }
+    return 0;
 }