diff --git a/src/c/a3.c b/src/c/a3.c
index 1af6471..e45115b 100644
--- a/src/c/a3.c
+++ b/src/c/a3.c
@@ -4,15 +4,15 @@
 #include <memory.h>
 
 void memdump(unsigned char *string) {
-    printf("ADDR    00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F  0123456789ABCDEF\n");
+    printf("ADDR           00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F  0123456789ABCDEF\n");
 
     int columns = 16;
     int rows = 4;
     char array[columns * rows];
 
-
     for(int i = 0; i < rows; i++) {
-        printf("0x%02x    ", string[i]);
+        printf("%p    ", (void *) &string[i * columns]);
+
         for (int j = i * columns; j < (i + 1) * columns; j++) {
             printf("%02x ", string[j]);
             if(string[j] < 0x20 || string[j] > 0x7e) array[j] = '.';
@@ -24,29 +24,19 @@ void memdump(unsigned char *string) {
             printf("%c", array[j]);
 
         }
-
         printf("\n");
-
-
     }
-
-
 }
 
 
 int memreplace(char *string, char cin, char cout, char **caddr) {
     int found = 0;
-    char *bla = NULL;
     for (int i = 0; i < strlen(string); ++i) {
         if(string[i] == cin) {
             found++;
-
-            //TODO: fix pointer assignment
-            //if(*caddr) free(caddr);
-            bla = &string[i];
-
+            string[i] = cout;
+            *caddr = &string[i];
         }
-        *caddr = bla;
     }
     return found;
 }
@@ -69,14 +59,13 @@ int main(int argc, char **argv) {
     printf("Ersetzen: '%c' mit '%c'\n", *argv[2], *argv[3]);
 
     unsigned char *copy = malloc(4 * 16 * sizeof(char));
-
     strcpy((char *) copy, argv[1]);
 
-    char **lastAddress = NULL;
-    int count = memreplace((char *) *copy, *argv[2], *argv[3], lastAddress);
+    char *lastAddress = NULL;
+    int count = memreplace((char *) copy, *argv[2], *argv[3], &lastAddress);
     printf("Suchzeichen wurde %i mal gefunden und ersetzt\n", count);
     //TODO: change type
-    printf("zuletzt an Addresse 0x%02x \n", (unsigned int) &lastAddress);
+    printf("zuletzt an Addresse %p \n", *lastAddress);
     memdump(copy);
 
     free(copy);