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Given a string , " This is a test" reverse it: " tset a si siht"Do this recursively.public class reverseStringRecursive { private static vo... 阅读全文
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就是permutations II考虑有重复字母的情况。String str = "someString"; char[] charArray = str.toCharArray();对char array进行排序:Arrays.sort(charArray)之后再把CharArray转化成stri... 阅读全文
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Given a sorted array arr[] and a number x, write a function that counts the occurrences of x in arr[]. Expected time complexity is O(Logn)Examples: I... 阅读全文
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Given a list of child->parent relationships, build a binary tree out of it. All the element Ids inside the tree are unique.Example:Given the following... 阅读全文
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Given an unsorted array of positive integers. Find the number of triangles that can be formed with three different array elements as three sides of tr... 阅读全文