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Time Limit: 2 s Memory Limit: 1024 MB Total points: 100

#6326. 构造凸序列

Statistics

给定两个整数序列 $L = (L_1, L_2, \dots, L_N)$ 和 $R = (R_1, R_2, \dots, R_N)$。请判断是否存在一个实数序列 $A = (A_1, A_2, \dots, A_N)$ 满足以下条件:

  • 对于所有满足 $1 \le i \le N$ 的整数 $i$,都有 $L_i \le A_i \le R_i$。
  • 对于所有满足 $2 \le i \le N - 1$ 的整数 $i$,都有 $A_{i-1} + A_{i+1} \ge 2A_i$。

输入格式

输入通过标准输入按以下格式给出:

$N$ $L_1 \ L_2 \ \dots \ L_N$ $R_1 \ R_2 \ \dots \ R_N$

  • 输入中的所有值均为整数。
  • $3 \le N \le 3 \times 10^5$
  • $1 \le L_i \le R_i \le 10^9$ ($1 \le i \le N$)

输出格式

如果存在满足条件的实数序列 $A$,输出 Yes。否则,输出 No

样例

样例输入 1

4
2 1 2 5
4 6 5 8

样例输出 1

Yes

样例输入 2

3
1 4 2
3 7 4

样例输出 2

No

说明

在第一个样例中,例如 $A = (4, \frac{3}{2}, 3, 7)$ 满足条件。

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