MPILOT – SPOJ

const   fi='';
        fo='';
        maxn=10000+3;
var     p,h:array[1..maxn] of longint;
        i,j,n,res,sum:longint;
        a,c:array[1..maxn] of longint;
        nh:longint;
procedure enter;
begin
        assign(input,fi);reset(input);
        readln(n);
        for i:=1 to n do read(a[i],c[i]);
        close(input);
end;
procedure swap(var x,y:longint);
var     tg:longint;
begin
        tg:=x;x:=y;y:=tg;
end;
function tinh(x:longint):longint;
begin
        exit(a[x]-c[x]);
end;
procedure downheap(i:longint);
var     j:longint;
begin
        j:=i + i;
        if j>nh then exit;
        if (j<nh) and ( tinh(h[j+1]) > tinh(h[j]) ) then inc(j);
        if tinh(h[i]) < tinh(h[j]) then
                begin
                        swap(h[i],h[j]);
                        downheap(j);
                end;
end;
procedure upheap(i:longint);
var     j:longint;
begin
        j:= i div 2;
        if i>1 then
        if tinh(h[i]) > tinh(h[j]) then
                begin
                        swap(h[i],h[j]);
                        upheap(j);
                end;
end;
function pop:longint;
begin
        pop:=h[1];
        h[1]:=h[nh];
        dec(nh);
        downheap(1);
end;
procedure push(i:longint);
begin
        inc(nh);
        h[nh]:=i;
        upheap(nh);
end;
procedure process;
begin
        for i:=1 to n do
                begin
                        inc(sum,a[i]);
                        push(i);
                        if i mod 2 = 1 then inc(res,tinh(pop) );
                end;
end;
procedure print;
begin
        assign(output,fo);rewrite(output);
        writeln(sum-res);
        close(output);
end;
begin
        enter;
        process;
        print;
end.

const fi=''; fo=''; maxn=10000+3; var p,h:array[1..maxn] of longint; i,j,n,res,sum:longint; a,c:array[1..maxn] of longint; nh:longint; procedure enter; begin assign(input,fi);reset(input); readln(n); for i:=1 to n do read(a[i],c[i]); close(input); end; procedure swap(var x,y:longint); var tg:longint; begin tg:=x;x:=y;y:=tg; end; function tinh(x:longint):longint; begin exit(a[x]-c[x]); end; procedure downheap(i:longint); var j:longint; begin j:=i + i; if j>nh then exit; if (j<nh) and ( tinh(h[j+1]) > tinh(h[j]) ) then inc(j); if tinh(h[i]) < tinh(h[j]) then begin swap(h[i],h[j]); downheap(j); end; end; procedure upheap(i:longint); var j:longint; begin j:= i div 2; if i>1 then if tinh(h[i]) > tinh(h[j]) then begin swap(h[i],h[j]); upheap(j); end; end; function pop:longint; begin pop:=h[1]; h[1]:=h[nh]; dec(nh); downheap(1); end; procedure push(i:longint); begin inc(nh); h[nh]:=i; upheap(nh); end; procedure process; begin for i:=1 to n do begin inc(sum,a[i]); push(i); if i mod 2 = 1 then inc(res,tinh(pop) ); end; end; procedure print; begin assign(output,fo);rewrite(output); writeln(sum-res); close(output); end; begin enter; process; print; end.