// 1024. Video Stitching

//

// You are given a series of video clips from a sporting event that lasted time seconds. These video clips can be overlapping with each other and have varying lengths.

//

// Each video clip is described by an array clips where clips[i] = [starti, endi] indicates that the ith clip started at starti and ended at endi.

//

// We can cut these clips into segments freely.

//

// For example, a clip [0, 7] can be cut into segments [0, 1] + [1, 3] + [3, 7].

// Return the minimum number of clips needed so that we can cut the clips into segments that cover the entire sporting event [0, time]. If the task is impossible, return -1.

//

//

//

// Example 1:

//

// Input: clips = [[0,2],[4,6],[8,10],[1,9],[1,5],[5,9]], time = 10

// Output: 3

// Explanation: We take the clips [0,2], [8,10], [1,9]; a total of 3 clips.

// Then, we can reconstruct the sporting event as follows:

// We cut [1,9] into segments [1,2] + [2,8] + [8,9].

// Now we have segments [0,2] + [2,8] + [8,10] which cover the sporting event [0, 10].

// Example 2:

//

// Input: clips = [[0,1],[1,2]], time = 5

// Output: -1

// Explanation: We cannot cover [0,5] with only [0,1] and [1,2].

// Example 3:

//

// Input: clips = [[0,1],[6,8],[0,2],[5,6],[0,4],[0,3],[6,7],[1,3],[4,7],[1,4],[2,5],[2,6],[3,4],[4,5],[5,7],[6,9]], time = 9

// Output: 3

// Explanation: We can take clips [0,4], [4,7], and [6,9].

//

//

// Constraints:

//

// 1 <= clips.length <= 100

// 0 <= starti <= endi <= 100

// 1 <= time <= 100

//

// Runtime 1 ms Beats 87.67%

// Memory 40.2 MB Beats 84.93%

class Solution {

private int[][] clips;

public int videoStitching(int[][] clips, int time) {

Arrays.sort(clips, (a, b) -> (a[0] - b[0]));

int ans = 0;

int index = 0;

int startTime = 0;

int endTime = 0;

while (startTime < time) {

while (index < clips.length && clips[index][0] <= startTime) {

endTime = Math.max(endTime, clips[index][1]);

index++;

}

if (startTime == endTime) return -1;

ans++;

startTime = endTime;

}

return ans;

}

}