I am compiling a cpp program with math.h using Arm performance library

In their example they compile programs in this way:

gcc code_with_math_routines.c -lamath -lm

But when I try g++ as follow:

g++ code_with_math_routines.cpp -lamath -lm

This will give an undefined reference error and the math function are not recognized.

collect2: error: ld returned 1 exit status

What is the difference between gcc and g++ command?