Compilare: user.cpp: In function ‘int main()’: user.cpp:29:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!p[a][b]) ^ user.cpp:29:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!p[a][b]) ^ user.cpp:31:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] p[a][b]=p[b][a]=true; ^ user.cpp:31:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] p[a][b]=p[b][a]=true; ^ user.cpp:31:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] p[a][b]=p[b][a]=true; ^ user.cpp:31:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] p[a][b]=p[b][a]=true; ^ user.cpp:33:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[a]--; ^ user.cpp:36:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[a]--; ^ user.cpp:37:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[b]--; ^ user.cpp:17:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%d%d\n",&n,&m); ^ user.cpp:27:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%c %c\n",&a,&b); ^