First, look at the title
1, probably next to each point to be able to mark a BFS.
2, you can think about why queue pop () is l ++;
3, or a character you have to pay attention to the next.
4, x, y, m, n, you have to figure out the ranks.
First, look at the title
1, probably next to each point to be able to mark a BFS.
2, you can think about why queue pop () is l ++;
3, or a character you have to pay attention to the next.
4, x, y, m, n, you have to figure out the ranks.