# 1711. Count Good Meals

<https://leetcode.com/problems/count-good-meals>

## Description

A **good meal** is a meal that contains **exactly two different food items** with a sum of deliciousness equal to a power of two.

You can pick **any** two different foods to make a good meal.

Given an array of integers `deliciousness` where `deliciousness[i]` is the deliciousness of the `i​​​​​​th​​​​`​​​​ item of food, return *the number of different **good meals** you can make from this list modulo* `109 + 7`.

Note that items with different indices are considered different even if they have the same deliciousness value.

**Example 1:**

```
**Input:** deliciousness = [1,3,5,7,9]
**Output:** 4
**Explanation:** The good meals are (1,3), (1,7), (3,5) and, (7,9).
Their respective sums are 4, 8, 8, and 16, all of which are powers of 2.
```

**Example 2:**

```
**Input:** deliciousness = [1,1,1,3,3,3,7]
**Output:** 15
**Explanation:** The good meals are (1,1) with 3 ways, (1,3) with 9 ways, and (1,7) with 3 ways.
```

**Constraints:**

* `1 <= deliciousness.length <= 105`
* `0 <= deliciousness[i] <= 220`

## ac

```java
```
