diff --git a/SDA.c b/SDA.c
index 1c60f2a..ff50bd2 100644
--- a/SDA.c
+++ b/SDA.c
@@ -24,4 +24,4 @@ void printSDA(struct sda s) {
     }
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/codeReader.c b/codeReader.c
index a698b10..d94d25b 100644
--- a/codeReader.c
+++ b/codeReader.c
@@ -12,7 +12,7 @@ unsigned int fromFile(char *path, struct program program) {
     FILE *fptr;
     fptr = fopen(path, "r+b");
     if (fptr == NULL) {
-        printf("Error: cannot open code file %s", path);
+        printf("Error: cannot open code file %s\n", path);
         exit(EXIT_FAILURE);
     }
     unsigned int buffer[4];
diff --git a/nja b/nja
old mode 100644
new mode 100755
diff --git a/nja-mac b/nja-mac
new file mode 100755
index 0000000..2a7ad14
Binary files /dev/null and b/nja-mac differ
diff --git a/njvm.c b/njvm.c
index 8dd700b..5d77770 100644
--- a/njvm.c
+++ b/njvm.c
@@ -7,10 +7,6 @@
 #include "codeReader.c"
 #include "SDA.c"
 
-//Comment to disable debug
-
-#define DEBUG
-
 // Stack
 struct stack stack;
 #define SIZE 1000
@@ -92,7 +88,7 @@ void execute(struct program program) {
                 stack.stack[fp + SIGN_EXTEND(IMMEDIATE(program.program[i]))] = pop(stack);
                 break;
             case POPL:
-                push(stack, stack.stack[fp + SIGN_EXTEND(IMMEDIATE(program.program[i]))]);
+                push(&stack, stack.stack[fp + SIGN_EXTEND(IMMEDIATE(program.program[i]))]);
                 break;
         }
     }
@@ -100,20 +96,18 @@ void execute(struct program program) {
     return;
 }
 
-#ifdef DEBUG
-
 void tests(void) {
     printf("Runnig debug mode\n");
-    int temp = fromFile("./prog1.bin", program);
+    int temp = fromFile("./prog2.bin", program);
     int sizeSDA = temp;
     unsigned int s[sizeSDA];
     sda.size = &temp;
     sda.sda = s;
     printProgram(program);
+    execute(program);
+    printSDA(sda);
 }
 
-#endif /* ifdef DEBUG */
-
 int main(int argc, char *argv[]) {
     // Initialize the Stack
     int size = SIZE;
@@ -131,41 +125,49 @@ int main(int argc, char *argv[]) {
     program.program = p;
     program.saveProgram = &saveProgram;
 
+    // Initialize runtime variables
+    int debug = 0;
+    int run = 0;
+    int sizeSDA;
 
-#ifdef DEBUG
-    tests();
-#endif /* ifdef DEBUG */
     if (argc > 1) {
-        if (strcmp(argv[1], "--version") == 0) {
-            version();
-        } else if (strcmp(argv[1], "--help") == 0) {
-            help();
-        } else if (strcmp(argv[1], "--prog1") == 0) {
-            copyToProgram(code1, sizeof(code1) / sizeof(code1[0]), program);
-            goto run;
-        } else if (strcmp(argv[1], "--prog2") == 0) {
-            copyToProgram(code2, sizeof(code2) / sizeof(code2[0]), program);
-            goto run;
-        } else if (strcmp(argv[1], "--prog3") == 0) {
-            copyToProgram(code3, sizeof(code3) / sizeof(code3[0]), program);
-            goto run;
-        } else {
-            printf("unknown command line argument '%s', try './njvm --help'", argv[1]);
+        for (int i = 1; i < argc; ++i) {
+            if (strcmp(argv[i], "--debug") == 0) {
+                debug = 1;
+            } else if (strcmp(argv[i], "--version") == 0) {
+                version();
+                return 0;
+            } else if (strcmp(argv[i], "--help") == 0) {
+                help();
+                return 0;
+            } else {
+                sizeSDA = fromFile(argv[i], program);
+                run = 1;
+            }
         }
-    } else {
-        run:
-//    Started
-        if (*program.saveProgram == 1) {
-            printf("Ninja Virtual Machine started\n");
-            printProgram(program);
-            execute(program);
-            printSDA(sda);
-        } else {
-            printf("Error: no code file specified\n");
-            return 1;
-        }
-//    Stopped
+    }
+
+    /*
+     * Debug mode
+     */
+    if (debug) {
+        tests();
+    }
+
+    /*
+     * Run program
+     */
+    if (run) {
+        printf("Ninja Virtual Machine started\n");
+        unsigned int s[sizeSDA];
+        sda.size = &sizeSDA;
+        sda.sda = s;
+        printProgram(program);
+        execute(program);
+        if (debug == 1) printSDA(sda);
         printf("Ninja Virtual Machine stopped\n");
-        return 0;
+    } else {
+        printf("Error: no code file specified\n");
+        return 1;
     }
 }
diff --git a/prog1.bin b/prog1.bin
deleted file mode 100644
index 8cc0eb1..0000000
Binary files a/prog1.bin and /dev/null differ