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# include <stdlib.h>
# include <stdio.h>
# include <string.h>
# include <stdbool.h>
int main (void) {
char * line = NULL;
size_t len = 0;
size_t str_len = 0;
/*
* Check whether a given number is a palindrome. We're only
* handling numbers consisting of ASCII digits.
*/
while ((str_len = getline (&line, &len, stdin)) != -1) {
str_len --; /* New line */
bool is_palindrome = !!str_len;
/*
* Check wether the characters are digits, and the same
* when counting from the end. Of strings of uneven length,
* don't check the middle character just yet.
*/
for (size_t i = 0; i < str_len / 2 && is_palindrome; i ++) {
if (line [i] < '0' || line [i] > '9' ||
line [i] != line [str_len - i - 1]) {
is_palindrome = false;
}
}
/*
* If we have an odd number of characters, check whether the middle
* character is a digit, or a dot -- but if it's a dot, the string
* should be at least two characters in length.
*/
if (is_palindrome && str_len % 2) {
size_t mid = str_len / 2;
if ((line [mid] < '0' || line [mid] > '9') &&
(line [mid] != '.' || str_len == 1)) {
is_palindrome = false;
}
}
printf ("%d\n", is_palindrome ? 1 : 0);
}
free (line);
return (0);
}
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