pow()函数计算幂。
此函数在<cmath>头文件中定义。
[数学] baseexponent = pow(base, exponent) [C++ 语言]
double pow(double base, double exponent); float pow(float base, float exponent); long double pow(long double base, long double exponent); Promoted pow(Type1 base, Type2 exponent); // 对于其他参数类型
从C ++ 11开始，如果传递给pow()的参数为long double，则返回类型Promoted 为long double。如果不是，则返回类型Promoted为double。
pow()函数采用两个参数：
base -基数
exponent -基数的指数
pow()函数返回以幂为底的底数。
#include <iostream>
#include <cmath>
using namespace std;
int main ()
{
double base, exponent, result;
base = 3.4;
exponent = 4.4;
result = pow(base, exponent);
cout << base << "^" << exponent << " = " << result;
return 0;
}运行该程序时，输出为：
3.4^4.4 = 218.025
#include <iostream>
#include <cmath>
using namespace std;
int main ()
{
long double base = 4.4, result;
int exponent = -3;
result = pow(base, exponent);
cout << base << "^" << exponent << " = " << result << endl;
//两个参数都是int
// pow()在本示例中返回double
int intBase = -4, intExponent = 6;
double answer;
answer = pow(intBase, intExponent);
cout << intBase << "^" << intExponent << " = " << answer;
return 0;
}运行该程序时，输出为：
4.4^-3 = 0.0117393 -4^6 = 4096