Compilare: main.cpp: In function 'int main()': main.cpp:12:23: warning: unused variable 'j' [-Wunused-variable] int n, a, b, i=1, j, cod, nr=0, nivel=0; ^ main.cpp:12:26: warning: unused variable 'cod' [-Wunused-variable] int n, a, b, i=1, j, cod, nr=0, nivel=0; ^~~ main.cpp:12:31: warning: unused variable 'nr' [-Wunused-variable] int n, a, b, i=1, j, cod, nr=0, nivel=0; ^~