Problem Link: http://oj.leetcode.com/problems/valid-palindrome/ The following two conditions would simplify the problem: only alphanumerci characters considered ignoring cases Given a string, we check if it is a valid palindrome by following rules: A…
Valid Palindrome Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a car" is not a palindrome. Note:Have you…
Problem Link: http://oj.leetcode.com/problems/interleaving-string/ Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. For example, Given: s1 = "aabcc", s2 = "dbbca", When s3 = "aadbbcbcac", return t…
Problem link: http://oj.leetcode.com/problems/reverse-words-in-a-string/ Given an input string, reverse the string word by word. For example, Given s = "the sky is blue", return "blue is sky the". LeetCode OJ supports Python now! The s…
Valid Palindrome Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a car" is not a palindrome. 验证回文与否,这个估计大家…
Problem Link: http://oj.leetcode.com/problems/palindrome-partitioning/ We solve this problem using Dynamic Programming. The problem holds the property of optimal sub-strcuture. Assume S is a string that can be partitioned into palindromes w1, ..., wn…
Problem Link: http://oj.leetcode.com/problems/palindrome-partitioning-ii/ We solve this problem by using Dynamic Programming. Optimal Sub-structure Assume a string S has the palindrome minimum cuts n, and S = W1 + W2 + ... + Wn where Wi is a palindro…
Problem link: http://oj.leetcode.com/problems/gas-station/ We can solve this problem by following algorithm. CompleteCircuit(gas, cost): let n be the number of stations // Check if there exists i such that A[i,n] >= 0 if (sum of gas) > (sum of cost)…
Problem link: http://oj.leetcode.com/problems/word-break-ii/ This problem is some extension of the word break problem, so the solution is based on the discussion in Word Break. We also use DP to solve the problem. In this solution, A[i] is not a bool…
