#include<cstdio>
#include<vector>
#include<cstring>
#include<queue>
using namespace std;
#define F1 "Sorted sequence determined after %d relations: "
#define F2 "Inconsistency found after %d relations."
#define F3 "Sorted sequence cannot be determined."
int n,m;
bool mp[26][26],vst[26];
int in[26];
queue<int> pre,topo;
int toposort()
{
    //for(int i=0;i<26;i++)
        //if(vst[i]) putchar(i+'A');
    //putchar('\n');
    int inn[26];
    memcpy(inn,in,sizeof(in));
    int tot=0;
    while(!topo.empty())
        topo.pop();
    for(int i=0;i<26;i++)
        if(vst[i]&&inn[i]==0){
            tot++;
            topo.push(i);
            //putchar(i+'A');
            if(tot>=2) return 0;
        }
    if(tot==0) return -1;
    while(!pre.empty())
        pre.pop();
    pre.push(topo.front());
    while(!topo.empty())
    {
        int cur=topo.front();
        topo.pop();
        int cnt=0;
        for(int i=0;i<26;i++)
        {
            if(mp[cur][i])
            {
                inn[i]--;
                if(!inn[i])
                {
                    cnt++;
                    tot++;
                    topo.push(i);
                    pre.push(i);
                }
            }
            if(cnt>=2) return 0;
        }
    }
    //printf("%d\n",tot);
    if(tot==n) return 1;
    return 0;
}
int main()
{
    scanf("%d%d",&n,&m);
    bool ok=false;
    for(int i=1;i<=m;i++)
    {
        getchar();
        char a,b;
        a=getchar();
        getchar();
        b=getchar();
        if(ok) continue;
        vst[a-'A']=vst[b-'A']=true;
        if(!mp[a-'A'][b-'A'])
            in[b-'A']++;
        else continue;
        if(mp[b-'A'][a-'A'] || b==a)
        {
            printf(F2,i);
            //return 0;
            ok=true;
        }
        mp[a-'A'][b-'A']=true;
        int ans=toposort();
        if(ans==0) continue;
        else if(ans==1)
        {
            printf(F1,i);
            while(!pre.empty())
            {
                putchar(pre.front()+'A');
                pre.pop();
            }
            putchar('.');
            //return 0;
            ok=true;
        }
        else {
            printf(F2,i);
            //return 0;
            ok=true;
        }
    }
    if(!ok) printf(F3);
    return 0;
}