Compilare: main.c: In function 'main': main.c:23:7: warning: array subscript has type 'char' [-Wchar-subscripts] ok[a][b]=ok[b][a]=1; ///marcam perechile interzise ^ main.c:23:10: warning: array subscript has type 'char' [-Wchar-subscripts] ok[a][b]=ok[b][a]=1; ///marcam perechile interzise ^ main.c:23:16: warning: array subscript has type 'char' [-Wchar-subscripts] ok[a][b]=ok[b][a]=1; ///marcam perechile interzise ^ main.c:23:19: warning: array subscript has type 'char' [-Wchar-subscripts] ok[a][b]=ok[b][a]=1; ///marcam perechile interzise ^ main.c:18:3: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d\n",&n,&m); ^~~~~~~~~~~~~~~~~~~~~~~~~~