545 - Heads

[..]

Can anyone tell me why do I get PE??

Code: Select all

int main()
{
    int N, expo;
    char start = 1;

    fscanf (stdin,"%d",&N);
    while(1) {
        if (fscanf (stdin,"%d",&N) == EOF)
              break;

        if (start) start = 0;
        else printf ("n");

        printf ("2^-%d = %.3fE-%dn", ?,?,?); // Spoiler removed :)
    }
    return 1;
}

[Ilham Kurnia]

try not to use
if (start) start = 0;
else printf("n");

[..]

Thanks for your reply, but this question is a multiple input question, so I add these 2 lines.

[Ilham Kurnia]

so, then, what about trying to print a line after every test case? there are occasions when the judge's output has an extra line...
(one more reason why they say not to worry when you get PE...)

<font size=-1>[ This Message was edited by: Ilham Kurnia on 2002-01-08 08:06 ]</font>

[..]

tried...but still PE......
I guess there is something wrong about the judge output.....
Anyway, thanks for your help~

[sjn]

program p545;
var
i,index,n:integer;
procedure solve;
var
temp:real;
i,count:integer;
begin
temp:=1;
count:=0;
for i:=1 to n do
begin
temp:=temp/2;
if temp<1
then begin
temp:=temp*10;
inc(count);
end;
end;
writeln (temp:0:3,'E-',count);
end;
begin
readln (index);
while not eof do
begin
read(n);
write('2^-',n,' = ');
solve;
end;
end.





Thanks in advance

[chang]

Pls check the output for input=6, output should be 1.563.
I also got WA before handling specially this input.

chang

[sjn]

Pls check the output for input=6, output should be 1.563.
I also got WA before handling specially this input.

chang

to chang:

thank you for replying
but i have done what you said, my program output is right
and alse WA so.....MY GOD!

[medv]

I think my program is correct, but I get WA. Help me, please.

(* @JUDGE_ID: 4406RA 545 PASCAL "Simple calculation" *)

program Heads_545;
var
c,n:integer;
res:extended;
begin
readln(n);
while (n > 0) do
begin
res := exp(-n * ln(2));
c := 0;
while (res < 1) do
begin
res := res * 10; Inc(c);
end;
writeln('2^-',n,' = ',res:0:3,'E-',c);
readln(n);
end;
end.

[Dominik Michniewski]

try to use log10() in place of log2() ....
it should be help
error was occur for n=5 and n=6 if I correct remember ...

good luck

[medv]

My answers are:
2^-6 = 1.563E-2
2^-5 = 3.125E-2
Are the correct?
If your 545 is accepted, send it for me to medv@roller.ukma.kiev.ua.

I tried a lot, but got WA. Help me, if you can.

Thank you.

[Dominik Michniewski]

I got right anserw on my computer too ....
But when OJ compiles and executes my program rounding error (maybe) occured ... in your case is the same
try to change base of logarithm and should be OK

[medv]

O-o-o How I tires of it! I tried it either in Pascal and in C, changed logarithm base system, even write the program that finds the solution without log and exp - straightforward, even I did rounding withount ROUND function - nothing helped me. I got WA! HEEELP!

This is my last program :

(* @JUDGE_ID: 4406RA 545 PASCAL "Simple calculation" *)

program Heads_545;
var
i,c,n,ri:integer;
ii,res:extended;
begin
readln(n);
while (n > 0) do
begin
if (n = 1) then
begin
writeln('2^-1 = 5.000E-1'); readln(n); continue;
end;
res := 1;
for i:=1 to n do
res := res / 2.0;
c := 0;
while (res < 1) do
begin
res := res * 10; Inc(c);
end;
ii := trunc(res);
write('2^-',n,' = ',ii:0:0,'.');
res := (res - ii) * 1000;
ri := round(int(res));
if (frac(res) >= 0.5) then Inc(ri);
if (ri < 10) then write('00') else
if (ri < 100) then write('0');
writeln(ri,'E-',c);
readln(n);
end;
end.

[medv]

Hi, everybody!

I posted here earlier the same question, but I haven't accepted this problem yet. Please, if smb solved it, send it's solution to me to medv@roller.ukma.kiev.ua. What is the trick?

I tried to send a lot of solutions:

1 Solution. I was told about errors at n=5 and n=6, so I wrote here the exact answers, but it didn't help.

program Heads_545;
var
c,n:integer;
res:extended;
begin
readln(n);
while (n > 0) do
begin
if (n = 5) then
begin
writeln('2^-5 = 3.125E-2');readln(n); continue;
end;
if (n = 6) then
begin
writeln('2^-6 = 1.563E-2');readln(n);continue;
end;
res := exp(-n * ln(2));
c := 0;
while (res < 1) do
begin
res := res * 10; Inc(c);
end;
writeln('2^-',n,' = ',res:0:3,'E-',c);
readln(n);
end;
end.


2 Solution (it's not mine, but it is also doesn't accepted)

program Heads_545;
var n,x,m:extended;
begin
while not eof do
begin
readln(n);
m := n*ln(2)/ln(10);
x := frac(m) - 1;
writeln('2^-',n:0:0,' = ',exp(-x*ln(10)):0:3,'E-', m-x :0:0 );
end;
end.


Regards,
Michael

[luizflip]

Did you write your program to work with multiple input?

I am having the same problem as you. I only get WA.