Compilare: user.cpp: In function ‘void solve()’: user.cpp:71:10: warning: unused variable ‘hi’ [-Wunused-variable] int hi; ^ user.cpp: In function ‘int main()’: user.cpp:127:9: warning: unused variable ‘i’ [-Wunused-variable] int i,j; ^ user.cpp:127:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp: In function ‘void read(int&, int&, int&)’: user.cpp:16:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&n,&m); ^ user.cpp:21:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&a[i][j]); ^