Compilare: user.c: In function ‘main’: user.c:16:7: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(dif+!(frecv[v[end]])<=c && end<z){ ^ user.c:17:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] dif+=!frecv[v[end]]; ^ user.c:18:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] frecv[v[end++]]++; ^ user.c:24:7: warning: array subscript has type ‘char’ [-Wchar-subscripts] frecv[v[beg]]--; ^ user.c:25:7: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!frecv[v[beg]]) ^ user.c:10:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d ", &z, &c); ^