namespace std {
using size_t = see [support.types.layout];
void* memcpy(void* s1, const void* s2, size_t n);
void* memmove(void* s1, const void* s2, size_t n);
char* strcpy(char* s1, const char* s2);
char* strncpy(char* s1, const char* s2, size_t n);
char* strcat(char* s1, const char* s2);
char* strncat(char* s1, const char* s2, size_t n);
int memcmp(const void* s1, const void* s2, size_t n);
int strcmp(const char* s1, const char* s2);
int strcoll(const char* s1, const char* s2);
int strncmp(const char* s1, const char* s2, size_t n);
size_t strxfrm(char* s1, const char* s2, size_t n);
const void* memchr(const void* s, int c, size_t n); void* memchr(void* s, int c, size_t n) const char* strchr(const char* s, int c) char* strchr(char* s, int c) size_t strcspn(const char* s1, const char* s2);
const char* strpbrk(const char* s1, const char* s2) char* strpbrk(char* s1, const char* s2) const char* strrchr(const char* s, int c) char* strrchr(char* s, int c) size_t strspn(const char* s1, const char* s2);
const char* strstr(const char* s1, const char* s2) char* strstr(char* s1, const char* s2) char* strtok(char* s1, const char* s2);
void* memset(void* s, int c, size_t n);
char* strerror(int errnum);
size_t strlen(const char* s);
}
#define NULL see [support.types.nullptr]