P1709 [SEERC 2003 / USACO5.5] Hidden Password

Sometimes the programmers have very strange ways of hiding their passwords. Billy "Hacker" Geits chooses a string S composed of L (5

Line 1: A single integer: L Line 2..?: All L characters of the the string S, broken across lines such that each line has 72 characters except the last one, which might have fewer.

Line 1: A single integer that is the start position of the first letter, as described above.

测试数据题目满足： $30 \%$ 的数据 $n \le {10}^4$。 $70 \%$ 的数据 $n \le {10}^5$。 $100 \%$ 的数据 $1 \le n \le 5 \times {10}^6$。 题目翻译来自 NOCOW。 USACO Training Section 5.5 // 20170523 新增数据四组