Program stergeri;
Var f,ff:text;
    n,m,k,kk,i,fff,kkk:longint;
    a,b:array[1..1000000] of longint;
Begin
 assign(f,'stergeri.in');
 reset(f);
 assign(ff,'stergeri.out');
 rewrite(ff);
 readln(f,n,m,k);
 kk:=k;
 for i:=1 to m do
    readln(f,a[i],b[i]);
 for i:=1 to m do
    if k>=a[i] then kk:=kk+(b[i]-a[i]+1);
 fff:=0;
 while(fff=0) do
    begin
     fff:=1;
     kkk:=kk;
     for i:=1 to m do
        if kk>b[i] then kk:=kk-(b[i]-a[i]+1)
                   else if (kk<=b[i])and(kk>=a[i]) then if kkk+(b[i]-a[i]+1)<=n then begin fff:=0; kkk:=kkk+(b[i]-a[i]+1); break; end;
     kk:=kkk-kk+k;
     if kk<>kkk then fff:=0;
    end;
 Writeln(ff,kk);
 close(ff);
 close(f);
End.