Compilare: user.cpp: In function ‘int main()’: user.cpp:10:15: warning: unused variable ‘l’ [-Wunused-variable] int i,n,j,l,nr,lin,col,x; ^ user.cpp:10:17: warning: unused variable ‘nr’ [-Wunused-variable] int i,n,j,l,nr,lin,col,x; ^ user.cpp:10:20: warning: unused variable ‘lin’ [-Wunused-variable] int i,n,j,l,nr,lin,col,x; ^ user.cpp:10:24: warning: unused variable ‘col’ [-Wunused-variable] int i,n,j,l,nr,lin,col,x; ^ user.cpp:10:28: warning: unused variable ‘x’ [-Wunused-variable] int i,n,j,l,nr,lin,col,x; ^ user.cpp:13:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d" ,&n); ^ user.cpp:16:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d" ,&mat[i][j]); ^