#arc102b. [arc102_b]All Your Paths are Different Lengths

[arc102_b]All Your Paths are Different Lengths

给你一个数LL, 构造一个有向图使得从11nn恰好有LL条路径且路径长度恰好为0L10到L - 1。边有边权。点数小于等于2020, 边数小于等于6060.