Algorithm
  • Introduction
  • First Chapter
  • Sorting Summary
  • LC 3 Longest Substring Without Repeating Characters
  • LC 5 Longest Palindromic Substring(M)
  • LC 17 Letter Combinations of a Phone Number(M)
  • LC 31 Next Permutation(M)
  • LC 44 Wildcard Matching(H)
  • LC 46 Permutations(M)
  • LC 47 Permutations II(M)
  • LC 53 Maximum Subarray(S)
  • LC 54 Spiral Matrix(M)
  • LC 60 Permutation Sequence(M)
  • LC 62 Unique Paths(M)
  • LC 63 Unique Paths II(M)
  • LC 64 Minimum Path Sum(M)
  • LC 79 Word Search(M)
  • LC 127 Word Ladder(M)
  • LC 131 Parlindrome Partitioning(M)
  • LC 152 Maximum Product Subarray(M)
  • LC 189 Rotate Array(S)
  • LC 186 Reverse Words in a String II(M)
  • LC 209 Minimum Size Subarray Sum(M)
  • LC 222 Count Complete Tree Nodes(M)
  • LC 287 Find the Duplicate Number(M)
  • LC 322 Coin Change(M)
  • LC 329 Longest Increasing Path in a Matrix(H)
  • LC 366 Find Leaves of Binary Tree(M)
  • LC 396 Rotate Function(M)
  • LC 435 Non-overlapping Intervals(M)
  • LC 442 Find All Duplicates in an Array(M)
  • LC 451 Sort Characters By Frequency(M)
  • LC 479 Largest Palindrome Product(M)
  • LC 518 Coin Change 2(M)
  • HR-Pairs
  • Tips
  • Template
  • A General Approach to Backtracking Questions
  • Useful Method
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Useful Method

  • String Class toCharArray() //get char array of a String charAt(int x) //get a char at the specific index length() //string length length //array size substring(int beginIndex) substring(int beginIndex, int endIndex) String.valueOf()/integer to string String.join(CharSequence delimiter, CharSequence... elements) 1.8

  • Character Character.isLetterOrDigit(ch) Character.toLowerCase(ch)

  • Integer Integer.valueOf()//string to integer

  • StringBuffer StringBuffer(str).reverse(); str.replaceAll("[^A-Za-z0-9]", "")

  • Arrays Arrays.sort() //sort an array Arrays.toString(char[] a) //convert to string Arrays.copyOf(T[] original, int newLength) Arrays.asList(T[]) System.arraycopy(Object src, int srcPos, Object dest, int destPos, int length)

  • Collections Collections.reverse(List)

PreviousA General Approach to Backtracking Questions

Last updated 5 years ago

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