Question

请C高手帮忙一下编一个简单的程序

编写一个函数int (char*source,char*s1,char*s2,int flag),把串source中与S1相同的串全部换为串S2，flag是大小写敏感的标志，函数返回被更换的数目
如source是intinINTch
S1为int
s2为FLOAT
如果大小写不敏感得FLOATinFLOATch
如果大小写敏感FLOATinINTch

Answer 1

虽然你小气的只给10分，但是还是帮你写了，交作业去吧，呵呵。

#include <stdio.h>
#include <string.h>

char* strcasestr(char* str1, char* str2)
{
int len = strlen(str2);
if(len == 0)
{
return NULL;
}
char *p = str1;
while(*p)
{
if(strncasecmp(p, str2, len) == 0)
return p;
p++;
}
return NULL;
}

int replace(char *source, char *s1, char *s2, int flag)
{
char buf[256] = {0};
int s1_len,ret = 0;
char *p;

s1_len = strlen(s1);
if(s1_len == 0)
return ret;
if(flag == 1)
{
p = strcasestr(source,s1);
}
else
{
p = strstr(source, s1);
}
if(p == NULL)
return ret;
strncpy(buf, source, p-source);
strcat(buf,s2);
strcat(buf,p+s1_len);
strcpy(source, buf);
ret = replace(source, s1, s2, flag) + 1;
return ret;
}

int main(int argc,char *argv[])
{
char la[256]="aaaflgjgiraaajlsdfaaadfgj";
char s[5]="AaA";
char b[5]="bbb";
int i;
i = replace(la, s, b, 1);
printf("%s\n%d\n",la, i);
return 0;
}