kdeng00
119 lines
2.7 KiB
C
119 lines
2.7 KiB
C
/*
|
|
*
|
|
* Exercise 3-3. Write a function expand(s1,s2) that expands shorthand
|
|
* notations like a-z in the string s1 into the equivalent complete
|
|
* list abc...xyz in s2. Allow for letters of either case and digits,
|
|
* and be prepared to handle cases like a-b-c and a-z0-9 and -a-z.
|
|
* Arrange that leading or trailing - is taken literally
|
|
*
|
|
*
|
|
* Author: Kun Deng
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
|
|
#define ARRAY_SIZE 1024
|
|
|
|
|
|
// If the characters are of the same type and
|
|
// if s is less than t, then the characters can
|
|
// be expanded.
|
|
// Returns 1 if expandable
|
|
int can_expand(char s, char t);
|
|
|
|
// Expands shorthand notations like a-z in the string s1 into
|
|
// the equivalent complete list abc...xyz in s2. The result will
|
|
// be stored in string s2
|
|
void expand(char *s1, char *s2);
|
|
|
|
|
|
int main()
|
|
{
|
|
char *s1 = "safeaf3-934bd-b-p0A-Fs0-9-Zaae-f-gsa";
|
|
char s2[ARRAY_SIZE];
|
|
|
|
printf("Before expand\n%s\n\n", s1);
|
|
expand(s1, s2);
|
|
printf("After expand\n%s\n", s2);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int can_expand(char s, char t)
|
|
{
|
|
int result = 0;
|
|
|
|
if ((48 <= s && s <= 57) && (48 <= t && t <= 57))
|
|
{
|
|
// Both characters are numbers
|
|
if (s < t)
|
|
{
|
|
// printf("%c (%d) and %c (%d) are numbers\n", s, s, t, t);
|
|
// Can be expanded
|
|
result = 1;
|
|
}
|
|
}
|
|
else if ((65 <= s && s <= 90) && (65 <= t && t <= 90))
|
|
{
|
|
// Both characters are uppercase characters
|
|
if (s < t)
|
|
{
|
|
// printf("%c and %c are uppercase letters\n", s, t);
|
|
// Can be expanded
|
|
result = 1;
|
|
}
|
|
}
|
|
else if ((97 <= s && s <= 122) && (97 <= t && t <= 122))
|
|
{
|
|
// Both characters are lowercase characters
|
|
if (s < t)
|
|
{
|
|
// Can be expanded
|
|
result = 1;
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
void expand(char *s1, char *s2)
|
|
{
|
|
int i, j;
|
|
for (i = 0, j = 0; s1[i] != '\0'; ++i)
|
|
{
|
|
if (s1[i] == '-' && s1[(i + 1)] != '\0' && i != 0 && s1[(i - 1)] != '-' && s1[(i + 1)] != '-')
|
|
{
|
|
char a1 = s1[(i - 1)];
|
|
char a2 = s1[(i + 1)];
|
|
|
|
if (can_expand(a1, a2) == 1)
|
|
{
|
|
// printf("Can expand %c (%d) and %c (%d)\n", a1, a1, a2, a2);
|
|
|
|
for (int k = (a1 + 1); k < a2; ++k)
|
|
{
|
|
char c = k;
|
|
|
|
// printf("%c %d\n", c, k);
|
|
|
|
s2[j++] = c;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// printf("Can't expand %c (%d) and %c (%d)\n", a1, a1, a2, a2);
|
|
s2[j++] = s1[i];
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// printf("Regular letter %c\n", s1[i]);
|
|
s2[j++] = s1[i];
|
|
}
|
|
}
|
|
|
|
s2[j] = '\0';
|
|
}
|