Compilare: main.cpp: In function 'int main()': main.cpp:20:15: warning: unused variable 'j' [-Wunused-variable] int n,m,i,j,nr=0,cer,l,r,len=0; ^ main.cpp:20:26: warning: unused variable 'l' [-Wunused-variable] int n,m,i,j,nr=0,cer,l,r,len=0; ^ main.cpp:20:28: warning: unused variable 'r' [-Wunused-variable] int n,m,i,j,nr=0,cer,l,r,len=0; ^ main.cpp:20:30: warning: unused variable 'len' [-Wunused-variable] int n,m,i,j,nr=0,cer,l,r,len=0; ^~~