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Is the Information Reliable?
Time Limit:3000MS  Memory Limit:131072K
Total Submit:605 Accepted:131

Description

The galaxy war between the Empire Draco and the Commonwealth of Zibu broke out 3 years ago. Draco established a line of defense called Grot. Grot is a straight line with N defense stations. Because of the cooperation of the stations, Zibu¡¯s Marine Glory cannot march any further but stay outside the line.

A mystery Information Group X benefits form selling information to both sides of the war. Today you the administrator of Zibu¡¯s Intelligence Department got a piece of information about Grot¡¯s defense stations¡¯ arrangement from Information Group X. Your task is to determine whether the information is reliable.

The information consists of M tips. Each tip is either precise or vague.

Precise tip is in the form of P A B X, means defense station A is X light-years north of defense station B.

Vague tip is in the form of V A B, means defense station A is in the north of defense station B, at least 1 light-year, but the precise distance is unknown.

Input

There are several test cases in the input. Each test case starts with two integers N (0 < N ¡Ü 1000) and M (1 ¡Ü M ¡Ü 100000).The next M line each describe a tip, either in precise form or vague form.

Output

Output one line for each test case in the input. Output ¡°Reliable¡± if It is possible to arrange N defense stations satisfying all the M tips, otherwise output ¡°Unreliable¡±.

Sample Input

3 4
P 1 2 1
P 2 3 1
V 1 3
P 1 3 1
5 5
V 1 2
V 2 3
V 3 4
V 4 5
V 3 5

Sample Output

Unreliable
Reliable

Source
POJ Monthly--2006.08.27, Dagger

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