How can I write real-time calculater _

gokhanyildirim99 (15)
Can I write real-time calculater with c programming ?

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salem c (3715)
You should know by now that just posting your homework and expecting a complete answer on a plate just isn't going to work.

Make an effort first.
Ganado (6849)
What does it mean to calculate something in real-time? Are there turn-based calculators?
jonnin (11495)
f is the only one you can do better than the built in language. the built in one does too much for integers, so an optimized integer version is worth writing; there are several examples on here. All the others are on the cpu circuits and too fast to try to beat out with code.

an example I played with a few years back. you can remove the higher powers for even more speed if not needed; all they are good for is like 2^60 type values, you can probably stop at 16 for most practical uses. (16 gets you x^31 or lower powers). 

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long long ipow(long long p, unsigned long long e) 
{ 
  const long long one = 1;
  const long long *lut[2] = {&p,&one};
  register long long result = 1;
    result *= lut[!(e&1)][0]; p *= p;
	result *= lut[!(e&2)][0]; p *= p;
	result *= lut[!(e&4)][0]; p *= p;
	result *= lut[!(e&8)][0]; p *= p;
	result *= lut[!(e&16)][0]; p *= p;
	result *= lut[!(e&32)][0]; p *= p;
	result *= lut[!(e&64)][0]; 	
	return result;
}


the same code can be used for doubles to integer powers.
if you want double powers, use the built in one, then you need the extra steps that it does.
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