Compilare: main.cpp: In function 'int main()': main.cpp:19:23: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 19 | for (int i=0;i<strlen(s);i++) { | ~^~~~~~~~~~ main.cpp:20:20: warning: array subscript has type 'char' [-Wchar-subscripts] 20 | fr1[s[i]]++; | ~~~^ main.cpp:23:23: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 23 | for (int i=0;i<strlen(s);i++) { | ~^~~~~~~~~~ main.cpp:24:20: warning: array subscript has type 'char' [-Wchar-subscripts] 24 | fr2[s[i]]++; | ~~~^