Given an undirected graph with `n` vertices via its adjacency matrix, and two vertices `s` and `t`, determine the **length of the shortest path** between `s` and `t`, measured as the number of edges. If `s == t`, the answer is `0`. If no path exists between `s` and `t`, print `-1`. Input: The first line contains three natural numbers, `n`, `s` and `t`, separated by spaces. The following `n` lines each contain `n` binary values: the adjacency matrix. - `1 <= n <= 50` - `1 <= s, t <= n` - use breadth-first search (BFS) implemented with an array Output: The program prints to standard output a single integer: the minimum path length from `s` to `t`, or `-1` if the two vertices are not in the same connected component. Example: Input: 6 1 6 0 1 1 0 0 0 1 0 0 1 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 0 0 1 0 1 0 0 0 0 1 0 Output: 4