Possible paths
Medium Accuracy: 52.31% Submissions: 1618 Points: 4

Given a directed graph and two vertices ‘u’ and ‘v’ in it. Find the number of possible walks from ‘u’ to ‘v’ with exactly k edges on the walk modulo 109+7.

Example 1:

Input 1: graph = {{0,1,1,1},{0,0,0,1},
{0,0,0,1}, {0,0,0,0}}, u = 0, v = 3, k = 2
Output: 2
Explanation: Let source ‘u’ be vertex 0,
destination ‘v’ be 3 and k be 2. The output
should be 2 as there are two walk from 0 to
3 with exactly 2 edges. The walks are {0, 2, 3}
and {0, 1, 3}.



You don't need to read or print anything. Your task is to complete the function MinimumWalk() which takes graph, u, v and k as input parameter and returns total possible paths from u to v using exactly k edges modulo 109+7.

Note: In graph, if graph[i][j] = 1, it means there is an directed edge from vertex i to j.

Expected Time Complexity: O(n3)
Expected Space Complexity: O(n3)

Constraints:
1 ≤ n ≤ 50
1 ≤ k ≤ n
0 ≤ u, v ≤ n-1

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