[LintCode] 最长公共子串

 1 class Solution {
 2 public:
 3     /**
 4      * @param A, B: Two string.
 5      * @return: the length of the longest common substring.
 6      */
 7     int longestCommonSubstring(string &A, string &B) {
 8         // write your code here
 9         int m = A.length(), n = B.length(), len = 0;
10         vector<int> cur(m + 1, 0);
11         for (int j = 1; j <= n; j++) {
12             int pre = 0;
13             for (int i = 1; i <= m; i++) {
14                 int temp = cur[i];
15                 cur[i] = (A[i - 1] == B[j - 1]) ? pre + 1 : 0;
16                 pre = temp;
17                 len = max(len, cur[i]);
18             }
19         }
20         return len;
21     }
22 };