Compilare: main.cpp: In function 'int main()': main.cpp:60:11: warning: array subscript has type 'char' [-Wchar-subscripts] 60 | fr[s[0]] = 1; | ~~~^ main.cpp:89:15: warning: array subscript has type 'char' [-Wchar-subscripts] 89 | fr[s[i]]++; | ~~~^ main.cpp: In function 'int invmod(int)': main.cpp:38:11: warning: 'd' is used uninitialized in this function [-Wuninitialized] 38 | euclid(a, MOD, d, x, y); | ~~~~~~^~~~~~~~~~~~~~~~~