Compilare: user.cpp: In function ‘void filll()’: user.cpp:130:26: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[a[i][j]] ++; ^ user.cpp: In function ‘void solve()’: user.cpp:172:9: warning: unused variable ‘i’ [-Wunused-variable] int i, j; ^ user.cpp:172:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp: In function ‘void readFile()’: user.cpp:30:30: 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:42:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%c", &c); ^