Compilare: main.cpp: In function 'int main()': main.cpp:14:10: warning: array subscript has type 'char' [-Wchar-subscripts] 14 | s[c[0]]=1; | ~~~^ main.cpp:18:33: warning: array subscript has type 'char' [-Wchar-subscripts] 18 | cnt=(cnt+1ULL*(sum-s[c[i]])*(n-i))%mod; | ~~~^ main.cpp:19:14: warning: array subscript has type 'char' [-Wchar-subscripts] 19 | s[c[i]]+=i+1; | ~~~^