647.c

Palindromic substring using dynamic programming

leetcode/src/647.c

@@ -0,0 +1,23 @@
+
+/* Author : Saurav Dubey */
+
+
+int countSubstrings(char* s) {
+    int len = strlen(s);
+    int i;
+    int count = 0;
+    for( i=0; i<len; i++){
+        // cases handled for both odd and even lenghted Palindrome
+
+        count += countPalin(s, i, i, len);
+        if(i!=len-1)
+            count += countPalin(s, i, i+1, len);
+    }
+    return count;
+}
+int countPalin(char *s, int head, int tail, int len){
+    int ret = (s[head]==s[tail])? 1:0 ;
+    if( ret && head-1>=0 && tail+1<len)
+        ret += countPalin(s, head-1, tail+1, len);
+    return ret;
+}