[动态规划] leetcode 1024 Video Stitching

problem:https://leetcode.com/problems/video-stitching/

         背包类型问题。可将长度视为背包容量，物体视为长条状的物体。

class Solution {
public:
    int videoStitching(vector<vector<int>>& clips, int T) {
        sort(clips.begin(), clips.end(), cmp);
        vector<int> dp(T + 1, -1);
        dp[0] = 0;
        for (int i = 0; i < clips.size(); i++)
        {
            int begin = clips[i][0];
            if (begin > T) break;
            int end = min(clips[i][1], T);
            if (dp[begin] == -1) continue;
            for (int t = begin + 1; t <= end; t++)
            {
                if (dp[t] == -1) dp[t] = dp[begin] + 1;
                else dp[t] = min(dp[t], dp[begin] + 1);
            }
        }
        return dp[T];
    }
};