📄 ex.dpr
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{
cuz x|x*10^n+y, so x|y. let y=kx
cuz kx|x*10^n+kx, so k|10^n
cuz no lead zero i.e. x>=10^(n-1) and y<10^n, so 1<=k<=9
if n=1, only k=1,2,5|10^1, then count(1,2,5)=9,4,1
if n=2, only k=1,2,4,5|10^2 then count(1,2,4,5)=90,40,15,10
if n=3 or more, at most k=1,2,4,5,8|10^3 then count(1,2,4,5,8)=(900,400,150,100,25)*10^(n-3)
}
program Ural_1385(Input,Output);
type
TIndex=Longint;
var
N:TIndex;
procedure Main;
begin
Readln(N);
if N=1 then
Write(9+4+1)
else if N=2 then
Write(90+40+15+10)
else
Write(900+400+150+100+25);
while N>3 do
begin
Dec(N);
Write(0);
end;
Writeln;
end;
begin
Main;
end.
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