Compilare: user.cpp: In function ‘int main()’: user.cpp:9:19: warning: unused variable ‘a’ [-Wunused-variable] int t,i,ok=1,j,k,a,nr; ^ user.cpp:9:21: warning: unused variable ‘nr’ [-Wunused-variable] int t,i,ok=1,j,k,a,nr; ^ user.cpp:23:42: warning: array subscript is above array bounds [-Warray-bounds] v[0]=s[k-2];v[1]=s[k-1];v[2]=s[k];v[3]='\0'; ^