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1.1 strstr
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void test_strstr()
{
char *str="Borland International";
char *str1="B",*ptr1;
char *str2="na",*ptr2;
char *str3="",*ptr3;
ptr1=strstr(str,str1);
printf("The substring1 is: %s\n", ptr1);//Borland International
ptr2=strstr(str,str2);
printf("The substring2 is: %s\n", ptr2);//national
ptr3=strstr(str,str3);
printf("The substring3 is: %s\n", ptr3); //Borland International
}
/*****************************************************
char *strstr( const char *string, const char *strCharSet );
Each of these functions returns a pointer to the first occurrence of strCharSet in string,
or NULL if strCharSet does not appear in string. If strCharSet points to a string of zero length,
the function returns string.
******************************************************/
1.2 atoiºÍ_itoa
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void char2int_1()
{
char* temp1="123";
int a1=atoi(temp1);
printf("char2int_1()\ta1+1=%
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#include <stdio.h>
#include <stdlib.h>
#define MAXSIZE 100
main()
{
FILE *fp;
if ( (fp = fopen( "c:\\a.txt", "r" )) == NULL ) printf("ERROR!\n");
int tmp[MAXSIZE];
int i;
for ( i=0; i<MAXSIZE; i++ )
{
tmp[i] = 0; ......
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int fgetc(FILE *stream);
int getc(FILE *stream);
int getchar(void);
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char *fgets(char * restrict s, int n, FILE * restrict stream);
char *gets(char *s);//¿ÉÄܵ¼ÖÂÒç³ö£¬ÓÃfgets´úÌæÖ®¡£
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int fscanf(FILE * r ......
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ASCII£¨American Standard Code for Information Interchange£¬ÃÀ¹úÐÅÏ¢»¥»»±ê×¼´úÂë£©Ê ......