#include <iostream>
using namespace std;
#define MAX 1001
int parent[MAX];
int dis[MAX];
int FindParent(int u)
{
	int p = u;
	while(parent[p] != 0)
		p = parent[p];
	return p;
}
bool check1(int u, int v, int w)
{
	int i, j, p;
	int disu = 0 ,disv = 0;
	for(i = u; i ; i = parent[i])
	{
		for(j = parent[v];j;j = parent[j])
			if(i == j)
				goto End;
	}
	End: p = i;
	for(i = u; i != p; i = parent[i])
		if(dis[u])
			disu += dis[u];
		else
			return true;

	for(i = v; i != p; i = parent[i])
		if(dis[v])
			disv += dis[v];
		else
			return true;

	if(w == disv - disu)
		return true;
	else
		return false;
}
bool check2(int u, int v)
{
	for(int i = parent[u]; i; i = parent[i])
		if(v == i)
			return false;
	return true;
}
int main()
{
	int N, M;
	int u, v, w;
	bool flag;
	while(scanf("%d%d", &N, &M))
	{
		getchar();
		flag = true;
		char ch;
		memset(parent, 0, sizeof(int)*(N+1));
		memset(dis, -1, sizeof(int)*(N+1));
		for(int i = 1; i <= M; ++i)
		{
			ch = getchar();
			if(ch == 'P')
			{
				scanf("%d%d%d",&u, &v, &w);
				getchar();
				if(FindParent(u) == FindParent(v))
				{
					if(FindParent(u) == 0)
					{
						parent[v] = u;
						dis[v] = w;
					}
					else if(!check1(u,v,w))
						flag = false;
				}
				else
				{
					parent[v] = u;
					dis[v] = w;
				}
			}
			else
			{
				scanf("%d%d",&u, &v);
				getchar();
				if(FindParent(u) == FindParent(v))
				{
					if(FindParent(u) == 0)
					{
						parent[v] = u;
						dis[v] = w;
					}
					else if(!check2(u,v))
						flag = false;
				}
				else
				{
					parent[v] = u;
					dis[v] = 0;
				}
			}
		}
		cout << (flag?"Reliable":"Unreliable") << endl;
	}
	return 0;
}