#include <iostream>
#include <stdio.h>
#include <queue>
using namespace std;
const int MAXN = 1000;
const int MAXM = 100000;
const int inf = 0x3fffffff;
struct node
{
    int to, next, w;
}edge[MAXM*3];
int box[MAXN+10], ecnt;
int dist[MAXN+10];
bool visit[MAXN+10];
int Count[MAXN+10];
int n, m;
void make_map(int from, int to, int w)
{
    edge[ecnt].to = to;
    edge[ecnt].w = w;
    edge[ecnt].next = box[from];
    box[from] = ecnt++;
}
bool spfa()
{
    queue<int>que;
    for(int i = 0; i <= n; i++)
    {
        visit[i] = false;
        dist[i] = inf;
    }
    dist[0] = 0;
    Count[0] = 1;
    que.push(0);
    visit[0] = true;
    while(!que.empty())
    {
        int x = que.front();
        que.pop();
        visit[x] = false;
        for(int i = box[x]; i+1; i = edge[i].next)
        {
            int e = edge[i].to;
            if(dist[e] > dist[x]+edge[i].w)
            {
                dist[e] = dist[x]+edge[i].w;
                if(!visit[e])
                {
                    visit[e] = true;
                    que.push(e);
                    Count[e]++;
                    if(Count[e] > n+1) return false;
                }
            }
        }
    }
    return true;
}
int main()
{
    //freopen("in.txt", "r", stdin);
    while(scanf("%d%d", &n, &m) != EOF)
    {
        memset(box, -1, sizeof(box));
        memset(Count, 0, sizeof(Count));
        ecnt = 0;
        char str[3];
        for(int i = 1; i <= m; i++)
        {
            scanf("%s", str);
            if(str[0] == 'P')
            {
                int u, v, w;
                scanf("%d%d%d", &u, &v, &w);
                make_map(u, v, -w);
                make_map(v, u, w);
            }
            else
            {
                int u, v;
                scanf("%d%d", &u, &v);
                make_map(u, v, -1);
            }
        }
        for(int i = 1; i <= n; i++) make_map(0, i, 0);
        if(spfa()) puts("Reliable");
        else puts("Unreliable");
    }
    return 0;
}