Lintcode: Longest Common Substring

 1 public class Solution {
 2     /**
 3      * @param A, B: Two strings.
 4      * @return: The length of longest common subsequence of A and B.
 5      */
 6     public int longestCommonSubstring(String A, String B) {
 7         // write your code here
 8         int[][] res = new int[A.length()+1][B.length()+1];
 9         int result = 0;
10         for (int i=0; i<=A.length(); i++) {
11             for (int j=0; j<=B.length(); j++) {
12                 if (i==0 || j==0) {
13                     res[i][j] = 0;
14                     continue;
15                 }
16                 if (A.charAt(i-1) != B.charAt(j-1)) res[i][j] = 0;
17                 else res[i][j] = res[i-1][j-1]+1;
18                 result = Math.max(result, res[i][j]);
19             }
20         }
21         return result;
22     }
23 }