#include <stdio.h>

#include <string.h>

#include <algorithm>

using namespace std;

const int N=5e3+;

struct Node{

  int l,r,v;

}p[N];

int a[N<<],cnt;

char s[];

int fa[N<<],sum[N<<];

int find(int x){

   if(x==fa[x])return x;

   int t=fa[x];

   fa[x]=find(fa[x]);

   sum[x]=(sum[x]+sum[t])%;

   return fa[x];

}

int main()

{

    int n;

    while(~scanf("%d%d",&n,&n)){

    cnt=;

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

      scanf("%d%d%s",&p[i].l,&p[i].r,s);

      if(s[]=='e')p[i].v=;

      else p[i].v=;

      --p[i].l;

      a[++cnt]=p[i].l,a[++cnt]=p[i].r;

    }

    sort(a+,a++cnt);

    cnt=unique(a+,a++cnt)-a-;

    for(int i=;i<=cnt;++i)fa[i]=i,sum[i]=;

    int ans=;

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

       p[i].l=lower_bound(a+,a++cnt,p[i].l)-a;

       p[i].r=lower_bound(a+,a++cnt,p[i].r)-a;

       int u=find(p[i].l),v=find(p[i].r);

       if(u==v){

          if((-sum[p[i].r]-sum[p[i].l])%!=p[i].v)break;

       }

       else if(u<v){

          fa[v]=u;

          sum[v]=sum[p[i].r]-sum[p[i].l]-p[i].v;

       }

       else{

          fa[u]=v;

          sum[u]=sum[p[i].l]-sum[p[i].r]+p[i].v;

       }

       ++ans;

    }

    printf("%d\n",ans);

    }

    return ;

}