== 1 == {{{ //strcpy char strcpy(char* dest, char* source) { char* dptr = dest; do { *dptr++ = *(source++); } while (*source); return dest; } }}} == 1-2 == {{{ //strlen char strlen(char* dest) { int length = 0; for (int i = 0; dest[i] != '\0'; i++) { length++; } return length; } }}} == 1-3 == {{{ //strcat char* strcat(char* dest, const char* source) { char* tmp = dest; while (*dest) dest++; while (*source != '\0') (*dest++ = *source++); return tmp; } }}} == 1-4 == {{{ //strcmp int strcmp(char* dest, const char* source) { do { if (*dest++ < *source++) return 1; else if (*dest++ > * source++) return -1; } while (*dest != '\0'); return 0; } }}}