Compilare: user.cpp: In function ‘int main()’: user.cpp:23:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] fra[a[i]]++; ^ user.cpp:27:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] frb[b[i]]++; ^ user.cpp:36:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(frb[a[i]] > 0) { ^ user.cpp:37:59: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(sz >= 0 && stk[sz] > a[i] && fra[stk[sz]] >= frb[stk[sz]] + 1) { ^ user.cpp:37:75: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(sz >= 0 && stk[sz] > a[i] && fra[stk[sz]] >= frb[stk[sz]] + 1) { ^ user.cpp:38:28: warning: array subscript has type ‘char’ [-Wchar-subscripts] frb[stk[sz]]++; ^ user.cpp:42:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] frb[a[i]]--; ^ user.cpp:44:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] fra[a[i]]--; ^ user.cpp:18:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%s %s " ,a + 1,b + 1); ^