C/C++——С±à̸CÓïÑÔº¯ÊýÄÇЩÊÂ(13)
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1. mallocº¯Êý
mallocº¯ÊýµÄ¹¦ÄÜÊÇÄÚ´æ·ÖÅ亯Êý£¬ÆäÓ÷¨Îª£ºvoid *malloc(unsigned size);³ÌÐòʵÀýÈçÏ£º
#include <stdio.h>
#include <string.h>
#include <alloc.h>
#include <process.h>
int main(void)
{
char *str;
if ((str = malloc(10)) == NULL)
{
printf("Not enough memory to allocate buffer\n");
exit(1); /* terminate program if out of memory */
}
strcpy(str, "Hello");
printf("String is %s\n", str);
free(str);
return 0;
}
2. memchrº¯Êý
memchrº¯ÊýµÄ¹¦ÄÜÊÇÔÚÊý×éµÄǰn¸ö×Ö½ÚÖÐËÑË÷×Ö·û£¬ÆäÓ÷¨Îª£ºvoid *memchr(void *s, char ch, unsigned n); ³ÌÐòʵÀý´úÂëÈçÏ£º
#include <string.h>
#include <stdio.h>
int main(void)
{
char str[17];
char *ptr;
strcpy(str, "This is a string");
ptr = memchr(str, 'r', strlen(str));
if (ptr)
printf("The character 'r' is at position: %d\n", ptr - str);
else
printf("The character was not found\n");
return 0;
}
3. memicmpº¯Êý
memicmpº¯ÊýµÄ¹¦ÄÜÊDZȽÏÁ½¸ö´®s1ºÍs2µÄǰn¸ö×Ö½Ú, ºöÂÔ´óСд£¬ÆäÓ÷¨Îª£ºint memicmp(void *s1, void *s2, unsigned n);³ÌÐòʵÀý´úÂëÈçÏ£º
#include <stdio.h>
#include <string.h>
int main(void)
{
char *buf1 = "ABCDE123";
char *buf2 = "abcde456";
int stat;
stat = memicmp(buf1, buf2, 5);
printf("The strings to position 5 are ");
if (stat)
printf("not ");
&
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1. kbhitº¯Êý
kbhitº¯ÊýÊǼì²éµ±Ç°°´Ïµļü£¬ÆäÓ÷¨Îª£ºint kbhit(void);³ÌÐòÀý×ÓÈçÏ£º
#include <conio.h>
int main(void)
{
c ......
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#ifdef __cplusplus
extern "C" {
#endif
/**** some declaration or so *****/
#ifde ......
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#include
<stdio.h>
int
main()
{
int
i = 0;
int
name[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
......
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1. ldexpº¯Êý
ldexpº¯ÊýµÄ¹¦ÄÜÊǼÆËãvalue*2µÄÃÝ£¬ÆäÓ÷¨Îª£ºdouble ldexp(double value, int exp);³ÌÐòʵÀýÈçÏ£º
......