水中的鱼

Given two strings S and T, determine if they are both one edit distance apart. [Thoughts] 这是个简化版。只要考虑几种可能， 如果s.length == t.length，只要看看不相同...

Given a positive integer  n , find the least number of perfect square numbers (for example,  1, 4, 9, 16, ... ) which sum to  n . For exa...

Given a string which contains only lowercase letters, remove duplicate letters so that every letter appear once and only once. You must mak...

Given a string array  words , find the maximum value of  length(word[i]) * length(word[j])  where the two words do not share common letters...

Given an input string, reverse the string word by word. For example, Given s = " the sky is blue ", return " blue is sky...

Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end ...

In English, we have a concept called  root , which can be followed by some other words to form another longer word - let's call this wor...

Given an encoded string, return it's decoded string. The encoding rule is:  k[encoded_string] , where the  encoded_string  inside the...

Given a string that contains only digits  0-9  and a target value, return all possibilities to add  binary  operators (not unary)  + ...

Given a list of  unique  words, find all pairs of  distinct  indices  (i, j)  in the given list, so that the concatenation of the two words...

Given two strings  s  and  t , write a function to determine if  t  is an anagram of  s . For example, s  = "anagram",  t  = ...

You are given a string,  S , and a list of words,  L , that are all of the same length. Find all starting indices of substring(s) in S tha...

Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n). For example...

Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeatin...

Given a string  S , find the longest palindromic substring in  S . You may assume that the maximum length of  S  is 1000, and there exists...

Write a function to find the longest common prefix string amongst an array of strings. » Solve this problem [解题报告] 又一个实现题。遍历字符串数组，每次用当...

Given a string  s  consists of upper/lower-case alphabets and empty space characters  ' ' , return the length of last word in the ...

Given  s1 ,  s2 ,  s3 , find whether  s3  is formed by the interleaving of  s1  and  s2 . For example, Given: s1  =  "aabcc"...

Implement strStr(). Returns a pointer to the first occurrence of needle in haystack, or  null  if needle is not part of haystack. » Sol...