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Re: c/2614: Error when calculating with long long int


On 23 Apr 2001 jacob.schultz@barconet.com wrote:

> There seems to be a problem when calculating with long longs. In a program I need to mask a number of bits from a long long, but something goes wrong. The calculation
> ((1<<n)-1)&m returns zero when n is 32 or larger, even if bits are set in m. Both n and m are unsigned long long int.

Try "(((1ull<<n) - 1) & m)".


Bernd


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