Number of Scoi2009windy

Digital DP, not really ...

The Calc function is divided into three parts:

The first part: statistics of the highest bit of 0, or the number of the most than the highest number of digits

The second part: Statistics the highest bit is 1 to a[len]-1, the direct call array can

The third part: the statistic and the X front (len-i) bit is same, but the remaining different satisfies the condition the number

Here's a trick, which is to be practical, just like the origin of imaginary numbers.

f[i,0] If there is no point in looking directly at it, will that number start at 0?

But if it does, f[i,j]:=f[i,j]+f[i-1,k]j can use it very well.

Or we can take f[i,j] as a string of length I, the number of strings that satisfy a condition with the first character J

Code:

1 varI,j,k,x,y:longint;2F:Array[-1.. the,-1.. the] ofLongint;3 functionCalc (x:longint): Longint;4  varI,j,len:longint;5 st:string;6A:Array[0.. the] ofLongint;7  begin8   ifx=0  ThenExit0);9 str (x,st);Tenlen:=Length (ST); Onecalc:=0; A    fori:=1  toLen DoA[i]:=ord (st[len+1-I.])- -; -    fori:=1  tolen-1  Do -     forj:=1  to 9  Do the Inc (Calc,f[i,j]); -    fori:=1  toa[len]-1  Do - Inc (Calc,f[len,i]); -    fori:=len-1 Downto 1  Do +    begin -      forj:=0  toa[i]-1  Do +      ifABS (a[i+1]-J) >=2  ThenInc (Calc,f[i,j]); A     ifABS (a[i+1]-a[i]) <2  ThenBreak ; at    End; -  End; - proceduremain; -  begin -     fori:=0  to 9  Dof[1, i]:=1; -     fori:=2  to Ten  Do in      forj:=0  to 9  Do -       fork:=0  to 9  Do to       ifABS (J-K) >=2  Thenf[i,j]:=f[i,j]+f[i-1, K]; + readln (x, y); -Writeln (Calc (y+1)-Calc (x)); the  End; * begin $ main;Panax Notoginseng  End.

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