# createHashMapFromArray

## Category
HashMap

## Arity
**Unary** — `createHashMapFromArray <array>`.

```
createHashMapFromArray <array>   // [key1, val1, key2, val2, ...]
```

## Description
Creates a new hashmap pre-populated from a flat array of alternating keys and values. The array must have an even number of elements: `[key1, val1, key2, val2, ...]`. If the array has an odd length, the last key without a value is ignored.

## How It Works
Iterates the array in pairs, inserting each `(key, value)` into a new `Dictionary<Value, Value>`. The resulting hashmap is mutable and owned by the current scheduler. Duplicate keys: later values overwrite earlier ones.

## Usage

### Create with initial data
```sqf
_map = createHashMapFromArray ["a", 1, "b", 2, "c", 3];
_map get "b";                  // 2
_map get "a";                  // 1
```

### Quick config
```sqf
_settings = createHashMapFromArray [
    "volume", 0.8,
    "music", true,
    "difficulty", "normal"
];
```

### From variables
```sqf
_name = "player";
_hp = 100;
_alive = true;
_entity = createHashMapFromArray [
    "name", _name,
    "hp", _hp,
    "alive", _alive
];
```

### Duplicate keys
```sqf
_map = createHashMapFromArray ["key", 1, "key", 2];
_map get "key";                // 2 (later overwrites earlier)
```

## Thread Safety
**Not thread-safe**. HashMap must be owned by the current scheduler.

## See Also
- [createHashMap](createHashMap.md) — create empty hashmap
- [get](get.md) — retrieve value by key
- [set](set.md) — store key-value pair