Compilare: user.cpp: In function ‘void fill(int, int, int)’: user.cpp:52:78: warning: array subscript has type ‘char’ [-Wchar-subscripts] else if(interior(xv,yv)&&a[xv][yv]!=a[x][y]&&h!=-1&&mat[a[xv][yv]]==0) ^ user.cpp:55:30: warning: array subscript has type ‘char’ [-Wchar-subscripts] mat[a[xv][yv]]=1; ^