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Diffstat (limited to 'Computer_Science/leetcode/5-longest_palindromic_substring.c')
-rw-r--r--Computer_Science/leetcode/5-longest_palindromic_substring.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/Computer_Science/leetcode/5-longest_palindromic_substring.c b/Computer_Science/leetcode/5-longest_palindromic_substring.c
new file mode 100644
index 0000000..ee65b8e
--- /dev/null
+++ b/Computer_Science/leetcode/5-longest_palindromic_substring.c
@@ -0,0 +1,34 @@
+void extend(char *s, int len, int i, int j, int *lo, int *hi)
+{
+ while(i >= 0 && i < len && s[i] == s[j]) {
+ i--;
+ j++;
+ }
+
+ if(j - i > *hi - *lo) {
+ *lo = i;
+ *hi = j;
+ }
+}
+
+char* longestPalindrome(char* s) {
+ int *lo, *hi;
+ int len = strlen(s);
+
+ lo = malloc(sizeof(int));
+ hi = malloc(sizeof(int));
+
+ *lo = *hi = 0;
+ if(len < 2)
+ return s;
+
+ for(int i = 0; i < len - 1; i++) {
+ extend(s, len, i, i, lo, hi);
+ extend(s, len, i, i + 1, lo, hi);
+ }
+
+ *(s + (*hi)) = '\0';
+ return s + *lo + 1;
+}
+
+