Compilare: user.cpp: In function ‘int main()’: user.cpp:30:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] k=a[c[i]]; ^ user.cpp:31:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] l=b[c[i]]; ^ user.cpp:16:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%c",&c[n]); ^