Compilare: main.cpp: In function 'int main()': main.cpp:18:21: warning: array subscript has type 'char' [-Wchar-subscripts] if(!f[ch]) ^ main.cpp:20:17: warning: array subscript has type 'char' [-Wchar-subscripts] f[ch]++; ^ main.cpp:27:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (t=0;t<L.size();t++){ ~^~~~~~~~~ main.cpp:37:68: warning: array subscript has type 'char' [-Wchar-subscripts] if (d[i][j]-d[i-m][j]-d[i][j-m]+d[i-m][j-m] != f[ch]) ^