#include <complex>
#include <cmath>
#include <cstdio>

int
main()
{
    printf("abs(-1.4) = %lf\n", abs(1.4));
    printf("abs(-1.4f) = %f\n", abs(1.4f));
    printf("abs(std::complex(-1.3, 2.3) = %lf\n",
           abs(std::complex<double>(-1.3, 2.3)));
}