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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
const ll mod=1000000007;
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=1010000;
VI e[N];
int n,m,a,b,cnt,dfn[N],low[N],st[N],bel[N],top,ind;
PII sg[N],vs[N];
int way[N];
ll dp[N];

bool ins[N];
void tarjan(int u) {
	dfn[u]=low[u]=++ind;
	ins[u]=1;
	st[++top]=u;
	rep(i,0,SZ(e[u])) {
		int v=e[u][i];
		if (!dfn[v]) tarjan(v),low[u]=min(low[u],low[v]);
		else if (ins[v]) low[u]=min(low[u],low[v]);
	} 
	if (dfn[u]==low[u]) {
		++cnt;
		VI z;
		while (1) {
			bel[st[top]]=cnt;
			z.pb(st[top]);
			ins[st[top]]=0;
			if (st[top--]==u) break;
		}
		vector<PII> seg;
		for (auto u:z) {
			if (u<=a) seg.pb(mp(u,u));
			for (auto v:e[u]) {
				if (bel[v]==bel[u]) continue;
				if (sg[bel[v]]!=mp(-1,-1)) {
					auto ss=sg[bel[v]];
					if (ss.fi>ss.se) {
						seg.pb(mp(1,ss.se));
						seg.pb(mp(ss.fi,a));
					} else {
						seg.pb(ss);
					}
				}
			}
		}
		//for (auto u:z) fprintf(stderr,"%d ",u); fprintf(stderr,":");
		sort(all(seg));
		//for (auto x:seg) fprintf(stderr," %d,%d",x.fi,x.se); fprintf(stderr,"\n");
		if (seg.empty()) sg[bel[u]]=mp(-1,-1);
		else {
			vector<PII> sseg;
			int pval=seg[0].se;
			int pre=seg[0].fi;
			for (auto x:seg) {
				if (x.fi<=pval+1) pval=max(pval,x.se);
				else {
					sseg.pb(mp(pre,pval));
					pre=x.fi; pval=x.se;
				}
			}
			sseg.pb(mp(pre,pval));
			assert(SZ(sseg)<=2);
			if (SZ(sseg)==1) {
				sg[bel[u]]=sseg[0];
			} else {
				assert(sseg[0].fi==1);
				assert(sseg[1].se==a);
				sg[bel[u]]=mp(sseg[1].fi,sseg[0].se);
			}
		}
		//fprintf(stderr,"faq %d : %d %d\n",u,sg[bel[u]].fi,sg[bel[u]].se);
	}
}

int main() {
	scanf("%d%d%d%d",&n,&m,&a,&b);
	for (int i=0;i<m;i++) {
		static char s[5];
		int u,v;
		scanf("%d%s%d",&u,s,&v);
		if (s[1]=='>') {
			e[v].pb(u);
		} else {
			e[v].pb(u); e[u].pb(v);
		}
	}
	for (int i=1;i<=n;i++) if (!dfn[i]) {
		tarjan(i);
	}
	ll ans=1;
	int emp=0,ful=0,cmid=0;
	map<PII,int> hs;
	int w=0;
	int mingap=n+1;
	int off=0;
	VI ps;
	for (int i=a+1;i<=a+b;i++) {
		auto x=sg[bel[i]];
		//fprintf(stderr,"%d %d\n",x.fi,x.se);
		if (x==mp(-1,-1)) emp++;
		else if (x==mp(1,a)) ful++;
		else {
			cmid++;
			vs[w++]=x;
			ps.pb(x.fi-1); ps.pb(x.se);
		}
	}
	ps.pb(0);
	ps.pb(a);
	sort(all(ps));
	ps.erase(unique(all(ps)),ps.end());
	a=SZ(ps)-1;
	for (int i=0;i<w;i++) {
		auto x=vs[i];
		vs[i].fi=lower_bound(all(ps),x.fi-1)-ps.begin();
		vs[i].se=lower_bound(all(ps),x.se)-ps.begin();
		x=vs[i];
		int gap=x.se-x.fi;
		if (gap<0) gap+=a;
		if (gap<mingap) {
			mingap=gap;
			off=(a-x.fi)%a;
		}
	}
	rep(i,0,w) {
		PII &x=vs[i];
		x.fi=(x.fi+off)%a,x.se=(x.se+off)%a;
		if (x.se<x.fi) x.se+=a;
		hs[x]++;
	}
	w=0;
	ans=0;
	for (auto x:hs) {
		w++;
		vs[w]=x.fi;
		way[w]=(powmod(2,x.se)-1)%mod;
		//printf("zz %d %d %d\n",w,vs[w].fi,vs[w].se);
	}
	for (int fa=0;fa<=vs[1].se;fa++) {
		vs[0].se=fa;
		dp[0]=1;
		ll sm=1;
		int r=0;
		for (int i=1;i<=w;i++) {
			while (vs[r].se<vs[i].fi) {
				sm=sm-dp[r];
				if (sm<0) sm+=mod;
				r++;
			}
			dp[i]=sm*way[i]%mod;
			sm=(sm+dp[i])%mod;
			if (vs[i].se==fa+a) ans=(ans+dp[i])%mod;
		//	printf("%d %d %lld\n",fa,i,dp[i]);
		}

	}
	ans=(ans+powmod(2,ful+cmid)-powmod(2,cmid))%mod;
	ans=ans*powmod(2,emp)%mod;
	if (ans<0) ans+=mod;
	printf("%lld\n",ans);
}