What is the C++ function to raise a number to a power?

In C++ the "^" operator is a bitwise XOR. It does not work for raising to a power. The x << n is a left shift of the binary number which is the same as multiplying x by 2 n number of times and that can only be used when raising 2 to a power, and not other integers. The POW function is a math function that will work generically.

std::pow in the <cmath> header has these overloads:

pow(float, float);
pow(float, int);
pow(double, double); // taken over from C
pow(double, int);
pow(long double, long double);
pow(long double, int);

Now you can't just do

pow(2, N)

with N being an int, because it doesn't know which of float, double, or long double version it should take, and you would get an ambiguity error. All three would need a conversion from int to floating point, and all three are equally costly!

Therefore, be sure to have the first argument typed so it matches one of those three perfectly. I usually use double

pow(2.0, N)

Some lawyer crap from me again. I've often fallen in this pitfall myself, so I'm going to warn you about it.

pow() in the cmath library. More info here. Don't forget to put #include<cmath> at the top of the file.