Compilare: main.cpp: In function 'int main()': main.cpp:16:40: warning: array subscript has type 'char' [-Wchar-subscripts] 16 | r+=((long long)(t-c[s[i]]) * (n-i))%mod; | ~~~^ main.cpp:20:22: warning: array subscript has type 'char' [-Wchar-subscripts] 20 | c[s[i]]+=i+1; | ~~~^ main.cpp:21:22: warning: array subscript has type 'char' [-Wchar-subscripts] 21 | c[s[i]]%=mod; | ~~~^