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#include <vector>
#include <iostream>
#include <array>
#include <cinttypes>
#include <cstring>
#include <climits>
#include <string>
using namespace std;
namespace wzor
{
	const int64_t MMOD = 1'000'000'007;
	struct Segment_tree
	{
		int left = 0;
		int right = 0;
		int64_t value = 0;
	};
	Segment_tree segments_to_use[480'000'000 / sizeof(Segment_tree)];
	int allocator_index = 1;

	Segment_tree* get_tree()
	{
		return &segments_to_use[allocator_index++];
	}

	void add_value(Segment_tree *tree, int64_t index_to_add, int64_t value_to_add, int st = 0, int en = MMOD - 1)
	{
		//std::cout << "ADD_VALUE: " << index_to_add << ' ' << st << ' ' << en << '\n';
		tree->value += value_to_add;
		if(tree->value >= MMOD)
			tree->value -= MMOD;
		if(st < en)
		{
			int mid = (st + en) / 2;
			if(index_to_add <= mid)
			{
				if(tree->left == 0)
					tree->left = allocator_index++;

				add_value(segments_to_use + tree->left, index_to_add, value_to_add, st, mid);
			}
			else
			{
				if(tree->right== 0)
					tree->right = allocator_index++;

				add_value(segments_to_use + tree->right, index_to_add, value_to_add, mid + 1, en);
			}
		}
	}

	int64_t get_sum(Segment_tree *tree, int st, int en, int a = 0, int b = MMOD - 1)
	{
		//std::cout << "GET SUM: " <<  st << ' ' << en << ' ' << a << ' ' << b << ' ' << (tree - segments_to_use)<< ' ' << tree->left << ' ' << tree->right << '\n';
		if(st <= a && b <= en)
		{
			return tree->value;
		}
		if(en < a || b < st)
		{
			return 0;
		}
		int mid = (a + b) / 2;
		int64_t res = 0;
		if(tree->left != 0)
			res += get_sum(&segments_to_use[tree->left], st, en, a, mid);
		/*else
			cout << "BAD L\n";*/

		if(tree->right != 0)
			res += get_sum(&segments_to_use[tree->right], st, en, mid + 1, b);
		/*else 
			cout << "BAD R\n";*/

		if(res >= MMOD) res -= MMOD;
		return res;
	}
	void print_tree(Segment_tree *tree, int a = 0, int b = MMOD - 1)
	{
		cout << tree->value << ' ' << a << ' ' << b << ' ' << tree->left << ' ' << tree->right << "\n";
		int mid = (a + b) / 2;
		if(tree->left != 0)
		{
			print_tree(&segments_to_use[tree->left], a, mid);
		}
		if(tree->right != 0)
		{
			print_tree(&segments_to_use[tree->right], mid + 1, b);
		}
	}
}
int64_t solve_wzor(int n, int* input)
{
	using namespace wzor;
	auto tree_even = get_tree();
	auto tree_odd = get_tree();
	add_value(tree_even, 0, 1);
	//print_tree(tree_even);
	int64_t prev_dp = 1;
	int64_t cur_value = 0;
	for(int i = 1; i <= n; ++i)
	{
		cur_value += input[i - 1];
		if(cur_value >= MMOD) cur_value -= MMOD;

		if(cur_value % 2 == 0)
		{
			prev_dp = get_sum(tree_even, 0, cur_value);
			if(cur_value + 1 <= MMOD)
				prev_dp += get_sum(tree_odd, cur_value + 1, MMOD);
			if(prev_dp >= MMOD) prev_dp -= MMOD;

			add_value(tree_even, cur_value, prev_dp);
		}
		else
		{
			prev_dp = get_sum(tree_odd, 0, cur_value);
			if(cur_value + 1 <= MMOD)
				prev_dp += get_sum(tree_even, cur_value + 1, MMOD);
			if(prev_dp >= MMOD) prev_dp -= MMOD;

			add_value(tree_odd, cur_value, prev_dp);
		}
		/*cout << "PREV DP: " << prev_dp << "\n";
		cout << "EVEN: " << i << "\n";
		print_tree(tree_even);
		cout << "ODD: " << i << "\n";
		print_tree(tree_odd);*/
	}
	return prev_dp;
}
#include <iostream>

int input[300100];
int main()
{
	int n;
	std::cin >> n;
	for(int i = 0; i < n; ++i)
	{
		std::cin >> input[i];
	}
	std::cout << solve_wzor(n, input) << '\n';
}