blob: 6e09de182911c1b3ab3730d86a6dde576f34dc4c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
#include <stdio.h>
/* The C Programming Language: 2nd Edition
*
* Exercise 2-5: Write the function any(s1,s2), which returns the first
* location of the string s1 where any character from the string s2 occurs, or
* -1 if s1 contains no characters from s2. (The standard library function
* strpbrk does the same job but returns a pointer to the location.)
*
* Answer: Similarly to squeeze(), any() uses two loops to do its job, but
* instead of changing the string, we're just returning the index of the first
* character found. If it's not found, it'll return a negative number. This
* is a common practice in functions that return integers since it gives
* programmers an easy case to check for: if any() returns anything less than
* zero, the characters in s2 weren't found.
*
*/
int any(char s1[], char s2[]) {
int i, j;
for (i = j = 0; s1[i] != '\0'; ++i) {
while (s2[j++] != '\0') {
if (s1[i] == s2[j]) {
return i;
}
}
j = 0;
}
return -1;
}
int main() {
char foo[80] = "argle bargle";
char bar[80] = "toobz";
int result;
if ((result = any(foo, bar)) != -1) {
printf("Found a match at position %d!\n", result);
} else {
printf("No match found.\n");
}
/* Should return a match at index 6. */
return 0;
}
|
