Compilare: user.cpp: In function ‘int main()’: user.cpp:11:11: warning: unused variable ‘f’ [-Wunused-variable] FILE *f = freopen ("unuzero.in", "r", stdin); ^ user.cpp:12:9: warning: unused variable ‘r’ [-Wunused-variable] int r = scanf ("%d\n", &n); ^ user.cpp:13:9: warning: unused variable ‘rr’ [-Wunused-variable] int rr = scanf ("%d %d\n", &P, &Q); ^ user.cpp:16:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp:18:9: warning: array subscript is below array bounds [-Warray-bounds] S[-1] = 0; ^