1543 - A simple problem
Time Limit : 2 Second
Memory Limit : 128 MB
Submission: 155
Solved: 8
- Description
- Given a permutation P of 1 to N, YY wants to know whether there exists such three elements P[i1], P[i2], P[i3] that P[i1]-P[i2]=P[i2]-P[i3], 1<=i1<i2<i3<=N.
- Input
- The first line is T(T<=60), representing the total test cases.
Each test case comes two lines, the former one is N, 3<=N<=10000, the latter is a permutation of 1 to N.
- Output
- For each test case, just output 'Y' if such i1, i2, i3 can be found, else 'N'.
- sample input
-
2 3 1 3 2 4 3 2 4 1
- sample output
-
N Y
- hint
- source
- “恒生杯”网络预选赛 | 非原创