I'm not able to do a random enumerator.
enum Notas {A=10, B=22, C=31, D=44, E=56};
It has this solution, but I need the enumerator values and here it is returning the rest of the calculation.
enum Notas {A=10, B=22, C=31, D=44, E=56, ULTIMO};
int teste = static_cast<Notas>(rand() % ULTIMO);
The problem seems to be that the possible values are not all valid. Instead of generating the random number directly, you will need a conversion.
Generate the number according to the number of Notes elements. If you have 5 grades, from A to E, generate a number from 0 to 4 using the:
enum Notas {A=10, B=22, C=31, D=44, E=56, ULTIMO};
#define NUMERO_DE_NOTAS 5
int teste = static_cast<Notas>(rand() % NUMERO_DE_NOTAS);
After that, you use the test to enter a switch and with each value return the correct note. If it is 0, it returns A, if it is 1, it returns B, etc ...