Cрочно, программа на цикл с параметром в Паскале

program chisla; var summa,n,y,i: longint; begin writeln ('daite N'); readln (n); for i: =1 to n do summa: =summa+i; {etot tikl dayot summu dlya nomera N, primer: n=5, summa=1+2+3+4+5=15; } y: =(n+1) /2; if y>summa then writeln ('Y > summa N ') else if y=summa then writeln ('Y=summa N') else writeln ('Y < summa'); readln; end. ya tak ponyal zadachu, esli ne tak, proshu popraviti. spasibo