# How to jointly check if the bits are set to an unsigned integer?

Given an unsigned integer, I would like to know if there is a way to determine if multiple bits are set in one operation. There's already an alternative way to do this by checking bit by bit (shown below), but I was wondering if there is a way to check all the bits collectively.

``````typedef enum Foo_X
{
Foo_0 = 0x1,
Foo_1 = 0x2,
Foo_2 = 0x4,
Foo_3 = 0x8,
} Foo_X;

bool CheckFoo ( UINT Value, Foo_X Foo_to_Check )
{
if (Value & Foo_to_Check)
{
// Foo_to_Check is present
return true;
}
}

void main()
{
UINT value = GetValueFromSomewhere();
if (CheckFoo(value, Foo_0) && CheckFoo(value, Foo_3))
// both Foo_0 and Foo_3 are present
else
// not both present
}
```

```

An example of using the collective method is shown below. Any ideas? TIA!

``````bool CheckFooTogether ( UINT Value, UINT Foos_to_Check )
{
// check value against Foos_to_Check collectively
}

void main()
{
UINT value = GetValueFromSomewhere();
if (CheckFooTogether (value, Foo_0 | Foo_3))
// both Foo_0 and Foo_3 are present
else
// not both present
}
```

```
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(Value and Foos_to_Check) == Foos_to_Check

+7

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``````(value & (FOO_0 | FOO_3)) == (FOO_0 | FOO_3)
```

```

returns `true`

when set `FOO_0`

and `FOO_3`

.

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You can accomplish this with a simple bitwise check `and`

:

``````bool CheckFooTogether ( UINT Value, UINT Foos_to_Check )
{
// check value against Foos_to_Check collectively
if( (Value & Foos_to_Check) == Foos_to_Check)
return true;
else
return false;
}

int main()
{
UINT value =  Foo_3 | Foo_2;
if (CheckFooTogether (value, Foo_0 | Foo_3))
// both Foo_0 and Foo_3 are present
cout << "both present";
else
// not both present
cout << "not both present";
}
```

```

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