#include <algorithm>

#include <bitset>

#include <cctype>

#include <cerrno>

#include <clocale>

#include <cmath>

#include <complex>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <ctime>

#include <deque>

#include <exception>

#include <fstream>

#include <functional>

#include <limits>

#include <list>

#include <map>

#include <iomanip>

#include <ios>

#include <iosfwd>

#include <iostream>

#include <istream>

#include <ostream>

#include <queue>

#include <set>

#include <sstream>

#include <stdexcept>

#include <streambuf>

#include <string>

#include <utility>

#include <vector>

#include <cwchar>

#include <cwctype>

#include <stack>

#include <limits.h>

using namespace std;

#define MAXN 1010

#define MAXM 200010

struct Edge

{

        int to,w,nxt;

} e[MAXM];

int i,n,m,a,b,c,tot;

int dis[MAXN],head[MAXN];

char opt[];

inline void add(int u,int v,int w)

{

        tot++;

        e[tot] = (Edge){v,w,head[u]};

        head[u] = tot;

}

inline bool spfa()

{

        int i,cur,v,w;

        queue<int> q;

        static bool inq[MAXN];

        static int cnt[MAXN];

        for (i = ; i <= n; i++)

        {

                dis[i] = ;

                q.push(i);

                inq[i] = true;

                cnt[i] = ;

        }

        while (!q.empty())

        {

                cur = q.front();

                q.pop();

                inq[cur] = false;

                for (i = head[cur]; i; i = e[i].nxt)

                {

                        v = e[i].to;

                        w = e[i].w;

                        if (dis[cur] + w > dis[v])

                        {

                                dis[v] = dis[cur] + w;

                                if (!inq[v])

                                {

                                        inq[v] = true;

                                        cnt[v]++;

                                        if (cnt[v] > n) return false;

                                        q.push(v);

                                }

                        }

                }

        }

        return true;

}

int main()

{

        while (scanf("%d",&n) != EOF && n)

        {

                tot = ;

                for (i = ; i <= n; i++)     head[i] = ;

                scanf("%d",&m);

                while (m--)

                {

                        scanf("%s",&opt);

                        if (strcmp(opt,"P") == )

                        {

                                scanf("%d%d%d",&a,&b,&c);

                                add(b,a,c);

                                add(a,b,-c);

                        } else

                        {

                                scanf("%d%d",&a,&b);

                                add(b,a,);

                        }

                }

                if (spfa()) printf("Reliable\n");

                else printf("Unreliable\n");

        }

        return ;

}