CF1373F.Network Coverage
提高+/省选-
通过率:0%
时间限制:2.00s
内存限制:256MB
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
The government of Berland decided to improve network coverage in his country. Berland has a unique structure: the capital in the center and n cities in a circle around the capital. The capital already has a good network coverage (so the government ignores it), but the i-th city contains ai households that require a connection.
The government designed a plan to build n network stations between all pairs of neighboring cities which will maintain connections only for these cities. In other words, the i-th network station will provide service only for the i-th and the (i+1)-th city (the n-th station is connected to the n-th and the 1-st city).
All network stations have capacities: the i-th station can provide the connection to at most bi households.
Now the government asks you to check can the designed stations meet the needs of all cities or not — that is, is it possible to assign each household a network station so that each network station i provides the connection to at most bi households.
Berland 政府决定改善本国的网络覆盖。Berland 的地理结构十分独特:首都位于中心,周围呈环形分布着 n 座城市。首都已有良好的网络覆盖(因此政府忽略首都),而第 i 座城市中有 ai 户家庭需要接入网络。
政府设计了一套建设计划:在每对相邻城市之间建造 n 个网络基站,每个基站仅为其所连接的两座城市提供服务。换言之,第 i 个网络基站仅服务于第 i 座城市和第 (i+1) 座城市(第 n 个基站则连接第 n 座城市和第 1 座城市)。
所有网络基站均有容量限制:第 i 个基站最多可为 bi 户家庭提供网络连接。
现在,政府请你判断:所设计的基站能否满足所有城市的网络需求?即,是否存在一种方案,将每一户家庭分配给某个网络基站,使得每个基站 i 所服务的家庭数不超过其容量 bi?
输入格式
The first line contains a single integer t (1≤t≤104) — the number of test cases.
The first line of each test case contains the single integer n (2≤n≤106) — the number of cities and stations.
The second line of each test case contains n integers (1≤ai≤109) — the number of households in the i-th city.
The third line of each test case contains n integers (1≤bi≤109) — the capacities of the designed stations.
It's guaranteed that the sum of n over test cases doesn't exceed 106.
第一行包含一个整数 t(1≤t≤104)—— 测试用例的数量。
每个测试用例的第一行包含一个整数 n(2≤n≤106)—— 城市与电站的数量。
每个测试用例的第二行包含 n 个整数(1≤ai≤109)—— 第 i 个城市中的家庭数量。
每个测试用例的第三行包含 n 个整数(1≤bi≤109)—— 设计的各电站的容量。
保证所有测试用例中 n 的总和不超过 106。
输出格式
For each test case, print YES, if the designed stations can meet the needs of all cities, or NO otherwise (case insensitive).
对于每个测试用例,如果所设计的车站能够满足所有城市的需求,则输出 YES,否则输出 NO(不区分大小写)。
输入输出样例
输入#1
5 3 2 3 4 3 3 3 3 3 3 3 2 3 4 4 2 3 4 5 3 7 2 2 4 4 5 2 3 2 3 2 7 2 1 1 10 10
输出#1
YES YES NO YES YES
说明/提示
In the first test case:
- the first network station can provide 2 connections to the first city and 1 connection to the second city;
- the second station can provide 2 connections to the second city and 1 connection to the third city;
- the third station can provide 3 connections to the third city.
In the second test case:
- the 1-st station can provide 2 connections to the 1-st city;
- the 2-nd station can provide 3 connections to the 2-nd city;
- the 3-rd station can provide 3 connections to the 3-rd city and 1 connection to the 1-st station.
In the third test case, the fourth city needs 5 connections, but the third and the fourth station has 4 connections in total.
在第一个测试用例中:
- 第一个网络基站可以向第一座城市提供 2 个连接,向第二座城市提供 1 个连接;
- 第二个基站可以向第二座城市提供 2 个连接,向第三座城市提供 1 个连接;
- 第三个基站可以向第三座城市提供 3 个连接。
在第二个测试用例中:
- 第 1 个基站可以向第 1 座城市提供 2 个连接;
- 第 2 个基站可以向第 2 座城市提供 3 个连接;
- 第 3 个基站可以向第 3 座城市提供 3 个连接,同时向第 1 座城市提供 1 个连接。
在第三个测试用例中,第四座城市需要 5 个连接,但第三个和第四个基站总共仅有 4 个连接。
输入解题思路,AI测评打分。不知道怎么写?