Compilare: user.cpp: In function ‘void quicksort(int*, int, int)’: user.cpp:20:45: warning: operation on ‘*(a + ((sizetype)(((unsigned int)iR) * 4u)))’ may be undefined [-Wsequence-point] {a[iL]=a[iL]+a[iR]-(a[iR]=a[iL]); ^ user.cpp: At global scope: user.cpp:30:6: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] main() ^