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#include <algorithm>
#include <iostream>
#include <vector>
#include <cmath>

using namespace std;

#define MODULO 1000000007

struct Sum
{
	int index, sum, scaled;
};

struct Tree
{
	int size;
	vector<int> values;

	Tree(int size)
	{
		this->size = 1 << (int)ceil(log2(size));
		values.resize(2 * this->size);
	}

	int query(int begin, int end)
	{
		return query(1, 0, size - 1, begin, end);
	}

	int query(int node, int left, int right, int begin, int end)
	{
		if(begin <= left && right <= end)
		{
			return values[node];
		}

		int middle = (left + right) / 2;
		int result = 0;
		
		if(begin <= middle)
		{
			result = query(2 * node, left, middle, begin, end);
		}

		if(end > middle)
		{
			result += query(2 * node + 1, middle + 1, right, begin, end);
			result %= MODULO;
		}

		return result;
	}

	void add(int node, int value)
	{
		node += size;

		while(node >= 1)
		{
			values[node] += value;
			values[node] %= MODULO;

			node /= 2;
		}
	}
};

#ifdef DEBUG
#include <functional>
#include <sstream>
#include <climits>
#include <random>
#include <chrono>

mt19937_64 randomEngine(chrono::system_clock::now().time_since_epoch().count());

template<class Type>
Type random(Type min, Type max)
{
	return uniform_int_distribution<Type>(min, max)(randomEngine);
}

void makeTest(stringstream& cout)
{
	int size = random<int>(5, 12);
	cout << size << '\n';

	while(size--)
	{
		cout << random<int>(0, MODULO - 1) << ' ';
	}

	cout << '\n';
}

void brute(stringstream& cin, stringstream& cout)
{
	int size;
	cin >> size;

	vector<int> values(size);

	for(auto& value : values)
	{
		cin >> value;
	}

	int result = 0;

	function<void(int)> solve = [&](int index)
	{
		if(index == size)
		{
			result++;
			result %= MODULO;

			return;
		}

		int sum = 0;

		for(int next = index; next < size; next++)
		{
			sum += values[next];
			sum %= MODULO;

			if(sum % 2 == 0)
			{
				solve(next + 1);
			}
		}
	};

	solve(0);

	cout << result << '\n';
}

void solve(stringstream& cin, stringstream& cout)
#else
void solve()
#endif
{
	int size;
	cin >> size;

	vector<int> values(size);
	vector<Sum> sums(size);

	int sum = 0;

	for(int index = 0; index < size; index++)
	{
		cin >> values[index];

		sum += values[index];
		sum %= MODULO;

		sums[index].index = index;
		sums[index].sum = sum;
	}

	sort(sums.begin(), sums.end(), [](Sum first, Sum second)
	{
		if(first.sum == second.sum)
		{
			return first.index < second.index;
		}

		return first.sum < second.sum;
	});

	int scaledSize = 0;
	sums[0].scaled = 0;
	
	for(int index = 1; index < size; index++)
	{
		if(sums[index].sum != sums[index - 1].sum)
		{
			scaledSize++;
		}
		
		sums[index].scaled = scaledSize;
	}

	sort(sums.begin(), sums.end(), [](Sum first, Sum second)
	{
		return first.index < second.index;
	});

	Tree good(scaledSize + 1);
	Tree bad(scaledSize + 1);

	int result;

	for(int index = 0; index < size; index++)
	{
		if(sums[index].sum % 2 == 0)
		{
			result = (1 + good.query(0, sums[index].scaled) + bad.query(sums[index].scaled, scaledSize)) % MODULO;
			good.add(sums[index].scaled, result);
		}
		else
		{
			result = (bad.query(0, sums[index].scaled) + good.query(sums[index].scaled, scaledSize)) % MODULO;
			bad.add(sums[index].scaled, result);

		}
	}

	cout << result << '\n';
}

int main()
{
#ifdef DEBUG
	for(int test = 1; test < INT_MAX; test++)
	{
		stringstream input, solveOutput, bruteOutput;
		makeTest(input);

		solve(input, solveOutput);
		input.seekg(0);

		brute(input, bruteOutput);
		input.seekg(0);

		if(solveOutput.str() == bruteOutput.str())
		{
			cout << "[#" << test << "] OK\n";
		}
		else
		{
			cout << "[#" << test << "] WRONG\nINPUT:\n" << input.str() << "SOLVE:\n" << solveOutput.str() << "BRUTE:\n" << bruteOutput.str();
			return 0;
		}
	}
#else
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	solve();
#endif
}