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#include<bits/stdc++.h>

using namespace std;

const int M=1e9+7;

int A[(int)3e5+5];
long long S[(int)3e5+5];

vector<pair<int,int> > P,NP;

long long T[3][(int)1e6+6];

struct seqtree{
	int siz3=1;
	void init(int n){
		while(siz3<n)siz3*=2;
	}
	int typ;
	
	void add(int x,int lx, int rx, int v,long long va){
		if(rx-lx==1)T[typ][x]=va;
		else{
			int m=(lx+rx)/2;
			if(v<m)add(2*x+1,lx,m,v,va);
			else add(2*x+2,m,rx,v,va);
			T[typ][x]=T[typ][2*x+1]+T[typ][2*x+2];
		}
	}
	
	long long suum(int x, int lx, int rx, int l, int r){
		if(l>=rx or r<=lx)return 0;
		if(lx>=l and rx<=r)return T[typ][x];
		
		int m=(lx+rx)/2;
		
		long long C=suum(2*x+1,lx,m,l,r);
		long long B=suum(2*x+2,m,rx,l,r);
		
		C+=B;C=(C+M)%M;
		
		return C;
	}


};

pair<int,int> G[(int)3e5+5];
/////typ/m-ce
seqtree st1,st2;
long long licz1(long long zero){
	long long Q=0;
	//<0,M) w parzystych
		//szukaj zero
	int p=-1;int k=P.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(P[m].first>=zero)k=m;
		else p=m;
	}
	int low=k;
	long long w=zero+M;w=(w+2*M)%(2*M);
	p=-1;k=P.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(P[m].first<w)p=m;
		else k=m;
	}
	int high=p;
	
	if(high>=low)Q+=st1.suum(0,0,st1.siz3,low,high+1);
	else{
		if(low!=P.size() and P[low].first<zero+M)Q+=st1.suum(0,0,st1.siz3,low,st1.siz3);
		if(high!=-1 and (zero+M>=2*M or P[high].first>=zero))Q+=st1.suum(0,0,st1.siz3,0,high+1);
	}
	//<M,2*M) w nieparzystych
	zero+=M;zero=(zero+2*M)%(2*M);
	p=-1;k=NP.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(NP[m].first>=zero)k=m;
		else p=m;
	}
	low=k;
	w=zero+M;w=(w+2*M)%(2*M);
	p=-1;k=NP.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(NP[m].first<w)p=m;
		else k=m;
	}
	high=p;
	
	if(high>=low)Q+=st2.suum(0,0,st2.siz3,low,high+1);
	else{
		if(low!=NP.size() and NP[low].first<zero+M)Q+=st2.suum(0,0,st2.siz3,low,st2.siz3);;
		if(high!=-1 and (zero+M>=2*M or NP[high].first>=zero))Q+=st2.suum(0,0,st2.siz3,0,high+1);
	}
	return Q;
}
long long licz2(long long zero){
	long long Q=0;
	int p=-1;int k=NP.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(NP[m].first>=zero)k=m;
		else p=m;
	}
	int low=k;
	long long w=zero+M;w=(w+2*M)%(2*M);
	p=-1;k=NP.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(NP[m].first<w)p=m;
		else k=m;
	}
	int high=p;
	
	if(high>=low)Q+=st2.suum(0,0,st2.siz3,low,high+1);
	else{
		if(low!=NP.size() and NP[low].first<zero+M)Q+=st2.suum(0,0,st2.siz3,low,st2.siz3);
		if(high!=-1 and (zero+M>=2*M or NP[high].first>=zero))Q+=st2.suum(0,0,st2.siz3,0,high+1);
	}
	zero+=M;zero=(zero+2*M)%(2*M);
	p=-1;k=P.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(P[m].first>=zero)k=m;
		else p=m;
	}
	low=k;
	w=zero+M;w=(w+2*M)%(2*M);
	p=-1;k=P.size();
	while(k-p>1){
		int m=(p+k)/2;
		if(P[m].first<w)p=m;
		else k=m;
	}
	high=p;
	
	if(high>=low)Q+=st1.suum(0,0,st1.siz3,low,high+1);
	else{
		if(low!=P.size() and P[low].first<zero+M)Q+=st1.suum(0,0,st1.siz3,low,st1.siz3);
		if(high!=-1 and (zero+M>=2*M or P[high].first>=zero))Q+=st1.suum(0,0,st1.siz3,0,high+1);
	}
	return Q;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie();
cout.tie();

	int n;cin>>n;
	P.push_back({0,0});
	for(int i=1;i<=n;i++){
		cin>>A[i];
		S[i]=S[i-1];
		S[i]+=A[i];
		S[i]=(S[i]+2*M)%(2*M);
		if(S[i]%2==0)P.push_back({S[i],i});
		else NP.push_back({S[i],i});
	}
	
	sort(P.begin(),P.end());
	for(int i=0;i<P.size();i++){
		G[P[i].second]={1,i};
	}
	sort(NP.begin(),NP.end());
	for(int i=0;i<NP.size();i++){
		G[NP[i].second]={2,i};
	}
	
	st1.typ=1;st2.typ=2;
	st1.init(P.size());st2.init(NP.size());
	
	if(G[n].first==1){
		st1.add(0,0,st1.siz3,G[n].second,1);
	}
	else st2.add(0,0,st2.siz3,G[n].second,1);
	for(int i=n;i>0;i--){
		long long Q=0;
		if(S[i-1]%2==0){
			Q=licz1(S[i-1]);Q=(Q+M)%M;
			st1.add(0,0,st1.siz3,G[i-1].second,Q);
		}
		else{
			Q=licz2(S[i-1]);
			Q=(Q+M)%M;
			st2.add(0,0,st2.siz3,G[i-1].second,Q);
		}
		if(i==1)cout<<Q;
	}
return 0;
}