#include <stdio.h>
#include <string.h>
#include <time.h>
#include <assert.h>
int 自作strcmp(const char* s1, const char* s2) {
while (*s1 && (*s1 == *s2)) {
s1++;
s2++;
}
return *s1 - *s2;
}
char *自作strcpy(char* dest, const char* src) {
while (*src != '\0') {
*dest = *src;
dest++;
src++;
}
*dest = '\0';
return dest;
}
size_t 自作strlen(const char *s) {
size_t len = 0;
while (*s != '\0') {
len++;
s++;
}
return len;
}
int 自作strncmp(const char* str1, const char* str2, size_t n)
{
for (size_t i = 0; i < n; i++){
if (str1[i] != str2[i]){
return str1[i] - str2[i];
}
if (str1[i] == '\0'){
return 0;
}
}
return 0;
}
char* 自作strncpy(char* dest, const char* src, size_t n) {
char* ret = dest;
while (n > 0 && *src != '\0') {
*dest++ = *src++;
n--;
}
while (n > 0) {
*dest++ = '\0';
n--;
}
return ret;
}
int 自作2引数(char *dst,char *src){
自作strcpy(dst,src);
return 自作strcmp(src,dst) ;
}
int 標準2引数(char *dst,char *src){
strcpy(dst,src);
return strcmp(src,dst) ;
}
int 自作3引数(char *dst,char *src){
size_t size = 自作strlen(src)+1;
自作strncpy(dst,src,size) ;
return 自作strncmp(dst,src,size);
}
int 標準3引数(char *dst,char *src){
size_t size = strlen(src)+1;
strncpy(dst,src,size) ;
return strncmp(dst,src,size);
}
typedef int (*関数ポインタ_型)(char *,char *);
static inline void 時間計測(
char *title,
関数ポインタ_型 計測対象関数,
char *dst,
char *src
){
clock_t start = clock();
for(int j = 0;j < 0x10000 ; j++){
const size_t max = strlen(src);
for(size_t i = 0;i < max ; i++){
if(計測対象関数(dst,src+i) != 0){
assert(0);
}
}
}
clock_t end = clock();
printf("%s\t:%.2f 秒\n",title, (double)(end - start) / CLOCKS_PER_SEC);
//printf("%s\t%8ld clock\n",title, end - start);
}
char *src =
"Jugemu Jugemu,"
"Gokō no Surikire,"
"Kaijarisuigyo no Suigyōmatsu,"
"Ungyōmatsu,"
"Fūraimatsu,"
"Kuunerutokoro ni Sumutokoro,"
"Yaburakōji no Burakōji,"
"Paipo Paipo,"
"Paipo no Shūringan,"
"Shūringan no Gūrindai,"
"Gūrindai no Ponpokopī no Ponpokona no Chōkyūmei,"
"Chōkyūmei no Chōsuke";
static char dst1[BUFSIZ];
static char dst2[BUFSIZ];
static char dst3[BUFSIZ];
static char dst4[BUFSIZ];
int main(void){
時間計測("標準2引数",標準2引数,dst2,src);
時間計測("標準3引数",標準3引数,dst4,src);
時間計測("自作2引数",自作2引数,dst1,src);
時間計測("自作3引数",自作3引数,dst3,src);
printf("dst1[0]=%c\n",dst1[0]);
printf("dst2[0]=%c\n",dst2[0]);
printf("dst3[0]=%c\n",dst3[0]);
printf("dst4[0]=%c\n",dst4[0]);
}
