#ifndef __STRING_H
#define __STRING_H
-int strlen(const char *str);
-void *memcpy(void *dest, const void *src, int len);
-void *memset(void *dest, int c, int len);
-int memcmp(const void *av, const void *bv, int len);
-char *strncat(char *dest, const char *src, unsigned int n);
-char *strcat(char *dest, const char *src);
-void strreverse(char s[]);
-void itoa(int n, char s[]);
+#include <stddef.h>
+void *memcpy(void *dest, const void *src, size_t len);
+void *memset(void *dest, int c, size_t len);
+void *memmove(void *dest, const void *src, size_t len);
+int memcmp(const void *av, const void *bv, size_t len);
+size_t strlen(const char *str);
+char *strncat(char *dest, const char *src, size_t n);
+char *strcat(char *dest, const char *src);
#endif /* __STRING_H */