解题步骤：

参考代码：

class Solution {
public:int findLength(vector<int>& nums1, vector<int>& nums2) {int m = nums1.size();int n = nums2.size();//多开一行，多开一列vector<vector<int>> dp(m + 1, vector<int>(n + 1));int ret = 0;for (size_t i = 1; i <= m; i++){for (size_t j = 1; j <= n; j++){if (nums1[i-1] == nums2[j-1]){dp[i][j] = dp[i - 1][j - 1] + 1;}else{dp[i][j] = 0;}ret = max(ret, dp[i][j]);}}return ret;}
};

你学会了吗？？？