标签：style blog io ar color sp for strong on
Problem
You are given a grid of numbers. A snake sequence is made up of adjacent numbers such that for each number, the number on the right or the number below it is +1 or -1 its value. For example,
1 3 2 6 8
-9 7 1 -1 2
1 5 0 1 9
In this grid, (3, 2, 1, 0, 1) is a snake sequence. Given a grid, find the longest snake sequences and their lengths
(so there can be multiple snake sequences with the maximum length).
Solution
1 public int findSnakeSequence(int[][] matrix) { 2 // List<List<Integer>> res = ArrayList<ArrayList<Integer>>(); 3 if(matrix == null || matrix.length == 0) { 4 return -1; 5 } 6 int m = matrix.length; 7 int n = matrix[0].length; 8 9 int[][] dp = new int[m][n]; 10 int globalMax = 0; 11 12 //initialize 13 dp[0][0] = 1; 14 for(int i=1; i<n; i++) { 15 if(Math.abs(matrix[0][i] - matrix[0][i-1]) == 1) 16 dp[0][i] = dp[0][i-1] + 1; 17 else 18 dp[0][i] = 1; 19 } 20 21 for(int i=1; i<m; i++) { 22 if(Math.abs(matrix[i][0] - matrix[i-1][0]) == 1) 23 dp[i][0] = dp[i-1][0] + 1; 24 else 25 dp[i][0] = 1; 26 } 27 28 for(int i=1; i<m; i++) { 29 for(int j=1; j<n; j++) { 30 int max = 1; 31 if(Math.abs(matrix[i][j] - matrix[i][j-1]) == 1) 32 max = dp[i][j-1] + 1; 33 if(Math.abs(matrix[i][j] - matrix[i-1][j]) == 1) 34 max = Math.max(max, dp[i-1][j] + 1); 35 dp[i][j] = max; 36 globalMax = Math.max(max, globalMax); 37 } 38 } 39 40 for (int i = 0; i < m; i++) { 41 for (int j = 0; j < n; j++) { 42 System.out.print(dp[i][j] + " "); 43 } 44 System.out.print("\n"); 45 } 46 47 return globalMax; 48 49 }
标签：style blog io ar color sp for strong on
原文地址：http://www.cnblogs.com/superbo/p/4112177.html
