# BitOperations.LeadingZeroCount Method

## Definition

## Overloads

LeadingZeroCount(UInt32) |
Counts the number of leading zero bits in an unsigned 32-bit integer mask. |

LeadingZeroCount(UInt64) |
Counts the number of leading zero bits in an unsigned 64-bit integer mask. |

## LeadingZeroCount(UInt32)

Important

This API is not CLS-compliant.

Counts the number of leading zero bits in an unsigned 32-bit integer mask.

```
public:
static int LeadingZeroCount(System::UInt32 value);
```

```
[System.CLSCompliant(false)]
public static int LeadingZeroCount (uint value);
```

`static member LeadingZeroCount : uint32 -> int`

`Public Shared Function LeadingZeroCount (value As UInteger) As Integer`

#### Parameters

- value
- UInt32

The mask.

#### Returns

The number of leading zero bits in a mask.

- Attributes

### Remarks

This method is similar in behavior to the x86 instruction LZCNT.

## LeadingZeroCount(UInt64)

Important

This API is not CLS-compliant.

Counts the number of leading zero bits in an unsigned 64-bit integer mask.

```
public:
static int LeadingZeroCount(System::UInt64 value);
```

```
[System.CLSCompliant(false)]
public static int LeadingZeroCount (ulong value);
```

`static member LeadingZeroCount : uint64 -> int`

`Public Shared Function LeadingZeroCount (value As ULong) As Integer`

#### Parameters

- value
- UInt64

The mask.

#### Returns

The number of leading zero bits in a mask.

- Attributes

### Remarks

This method is similar in behavior to the x86 instruction LZCNT.