uses crt; var n,i,s,d,max,j:longint; st:string; BEGIN clrscr; repeat write('Nhap chuoi: '); readln(st); n:=length(st); if frac(sqrt(n))<>0 then writeln('Vui long nhap lai'); until frac(sqrt(n))=0; n:=trunc(sqrt(n)); for i:=1 to n do begin s:=0; for j:=0 to n-1 do s:=s+ord(st[j*n+i]); if s > max then begin max:=s; d:=i; end; end; while d<=n*n do begin write(st[d],' '); inc(d,n); end; writeln; write(max); readln; END. 0*3+1 1*3+1 2*3+1 0*3+2 1*3+2 ... 1 4 7 2 5 8 3 6 9