POJ 3264(STRMQ)

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for j:=1 to ln(n)/ln(2)

for i:=1 to n-(1 shl j)+1 do

f[i,j]:=min(f[i,j-1],f[i+(1 shl (j-1),j-1];

f[l,r]:=min(f[l,j],f[r-(1 shl j)+1,j]; j=ln(r-l+1)/ln(2);

ln(n)/ln(2)=log(2,n);

Program lineup;const   maxn=50000;   maxq=200000;   maxh=1000000;var   n,q,i,j,l,r,k:longint;   a:array[1..maxh] of longint;   f,h:array[1..maxh,0..16] of longint;//f mintall h hightallfunction min(a,b:longint):longint;begin   if a<b then exit(a) else exit(b);end;function max(a,b:longint):longint;begin   if a>b then exit(a) else exit(b);end;begin   read(n,q);   for i:=1 to n do   begin      read(a[i]);      f[i,0]:=a[i];      h[i,0]:=a[i];   end;   for j:=1 to trunc(ln(n)/ln(2)) do   //f[i,j]:=min(f[i,j-1],f[i+2^(j-1),j-1] i<=n-2^j      for i:=1 to n-(1 shl j)+1 do      begin         f[i,j]:=min(f[i,j-1],f[i+1 shl (j-1),j-1]);         h[i,j]:=max(h[i,j-1],h[i+1 shl (j-1),j-1]);      end;   for i:=1 to q do   begin      read(l,r);      j:=(r-l+1);      j:=trunc(ln(j)/ln(2));      writeln(max(h[l,j],h[r-1 shl j +1,j])-min(f[l,j],f[r-1 shl j +1,j]));   end;end.