Can`t understand what is the problem

#include <stdio.h>
#include <math.h>

int main()
{
    unsigned long long int a[4096], b;
    int counter=0;
    while(scanf("%llu", &b))
    {
        a[counter]=b;
        counter++;
    }

    for(int i=counter-1; i>=0; i--)
        printf("%.15Lg\n", (long double)sqrt(a[i]));
    return 0;
}

Сan somebody tell whether it may be several current users at once?
Может кто нибудь сказать, может ли быть несколько текущих пользователей сразу?

Edited by author 01.02.2014 02:35

I tried to solve it with (dp[i] = sum_j(max(dp[j - 1], dp[i - j])) + 10) formula, but the way of getting the math expectation as max(dp[A], dp[B]) isn't right. Ho to do it? What is the formula..?

please, help me... :(

В FPC все работает, здесь же ...

Вот код, помогите
program f1;
var f,f2:text;
i,j:integer;
a:array[1..130000] of real;
begin
assign(f,'input.txt');
reset(f);
i:=0;
While not eof(f) do begin
                    inc(i);
                    read(f,a[i]);
                    end;
close(f);
assign(f2,'output.txt');
rewrite(f2);
For j:=i downto 1 do

writeln(f2,sqrt(a[j]):0:4);
close(f2);
End.

Do NOT use STL's strings, use standart C char arrays instead. That makes a HUGE difference in the time and memory complexity. I hope that this will be helpful to somebody:)

I tried to figure it out, how 1 tree and two sticks with the length of 2 can form the area more than 4? The largest area would be rectangle. What is the trick on this problem, can anybody explain with Geometry language.

Thanks.

Edited by author 30.01.2014 20:18

It keeps saying that my program produces incorrect solutions. Anyone else is having the same issue?

#include <stdlib.h>
#include <stdio.h>

int main() {
  int start, change, N, sum;
  scanf("%d", &N);
  if (abs(N) <= 10000) {
    change = N > 1 ? 1 : -1;
    for (start = 1; start != (N + change); start += change)
      sum += start;
    printf("%d\n", sum);
  }
  return 0;
}

#include <iostream>
#include <math.h>
using namespace std;

int main(int argc, char* argv[])
{
int N,Sum=0;
cout<<"Введите значение"<<endl;
cin>>N;
if(N>0 && N<=abs(1000))
{
 for(int i=0;i<=N;i++)
 {
    Sum+=i;
 }
 cout<<Sum;
}
if(N<0 && N<=abs(-1000))
{
  for(int j=0;j>=N;j--)
 {
    Sum+=j;
 }
cout<<Sum;
}    getch();
        return 0;
}

Edited by author 05.07.2013 20:36

Edited by author 05.07.2013 20:38

The Laplacian matrix does not have always N * M lines/columns.

 Извените, чо пишу на русском - по другому не умею.
 По поводу теста №2, в котором на вход подается 0, а правильным решением является пустая строка. Лично мое мнение: результатом должен быть массив длиной 1 с первым элементом равным 1.
Объясню:
 В условии задачи сказано, что входными данными являются число N(длина массива) и элементы этого массива. Предполагается, что N может быть равно 0.
 Массив поступает в функцию, которая возвращает массив, первым элементом которого является длина входного массива. Из этого можно зделать вывод, что, если на вход задачи может поступить массив, у которого указана длина 0, то и функция при обрабоке этого массива должна вернуть массив длиной 1 с первым элементом равным длинне массива, тоесть 0.
 После обработки этого массива функцией и получится массив длиной 1 с первым элементом равным 1.
 Лично я не догадался, что результатом будет пусая строка (пришлось подсмотреть на форуме).

Will Timus Online Judge support Nodejs?

Where i`m wrong?

#include <iostream>
#include <cmath>
#include <iomanip>

using namespace std;

int main()
{
    double t = 0;
    double eps;
    double x, y;
    cin>>x>>y>>eps;


    eps=eps*0.001;
    while(1)
    {
        double c = cos(t) - y;
        double d = sin(sqrt(t)) - x ;
        if( c*c+d*d > eps/2)
            t+=0.007;
        else
        {
            break;
        }
    }
    cout<<fixed<<setprecision(5)<<t;
    return 0;
}
Can someone tell what is wrong or give some tests?(my mail kilik94@yandex.ru) Thanks in advance!

Edited by author 07.12.2013 01:58

How to solve this problem?

Edited by author 29.09.2013 08:45

Edited by author 29.09.2013 08:45

I used such variables:
map<string,int> id;
set<string> list[1003];
map<string,int> mp;
vector<string> res;
but got TL test 10. Can i get AC with same solution?

If you have WA3 try this:
1 3 5
1
4
5
7
Right answer is 1

There *is* a period of 9973, but not for the given function.

Let's denote 9973 as M.

//////////////////////////////////////////////////////////////////////////
//In short////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////

1. g(n) is linear by f(n - 1), and g(x, y) = g(x mod M, y), which means we can find such A and B (in O(M)) that f(x + M) = (A * f(x) + B) mod M.

2. Having found such A and B, it's easy to show that for p > 0, f(p * M) = B * (A^(p-1) + A^(p-2) + .. + A^2 + A + 1) mod M.
I'm not sure if the last sum can be calculated in O(1), but it surely can be found in O(M).

3. So, we calc A and B, read N, find f(N - N % M) and then iterate till N in O(M), resulting with overall O(M).


//////////////////////////////////////////////////////////////////////////
//In detail///////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////

//////
//1.//
//////

Let's assume we know f(i) and wish to find f(i+1).
Easy to see, g(x, y) = g(x mod M, y). This is why,

f(i + 1) = g(i + 1, f(i)) = g((i + 1) mod M, f(i)).

Let's denote (i + 1) mod M as j.

f(i + 1) = g(j, f(i)) =  ((f(i) - 1) * j^5 + j^3 – j * f(i) + 3 * j + 7 * f(i)) mod M

f(i + 1) = f(i) * (j^5 - j + 7) + (-j^5 + j^3 + 3 * j) mod M

f(i + 1) = f(i) * ((j^5 - j + 7) mod M) + (-j^5 + j^3 + 3 * j) mod M

Remembering that j = (i + 1) mod M, let us denote

U(i) = (j^5 - j + 7) mod M,
V(i) = (-j^5 + j^3 + 3 * j) mod M.

As a result:

f(i + 1) = U(i) * f(i) + V(i)

Note that for any i, we calculate U(i) and V(i) in O(1) time.
Also note that U(i) = U(i mod M) and V(i) = V(i mod M):

f(i + 1) = U(i mod M) * f(i) + V(i mod M)

Let's consider some certain x, and let's denote f(x) as X.

f(x+0) == X == 1 * X + 0 == (a0 * X + b0)    (mod M)
f(x+1) == U(0) * f(x+0) + V(0) == (a1 * X + b1)    (mod M)
f(x+2) == U(1) * f(x+1) + V(1) == (U(1) * a1) * X + (U(1) * b1 + V(1)) == (a2 * X + b2)    (mod M)
f(x+3) == U(2) * f(x+2) + V(2) == (U(2) * a2) * X + (U(2) * b2 + V(2)) == (a3 * X + b3)    (mod M)
f(x+4) == U(3) * f(x+3) + V(3) == (U(3) * a3) * X + (U(3) * b3 + V(3)) == (a4 * X + b4)    (mod M)
...
f(x+M) == (aM * X + bM))    (mod M)

Note that aM and bM do not depend on x - this is the key point!

Let's denote aM as A and bM as B. Each iteration above needs O(1) time, so we found A and B in O(M), such that for any x,

f(x+M) = (A * f(x) + B) mod M

//////
//2.//
//////

Consider the following sequence

f(0 * M) == 0    (mod M)
f(1 * M) == A * f(0 * M) + B == B    (mod M)
f(2 * M) == A * f(1 * M) + B == A * B + B == B * (A + 1)    (mod M)
f(3 * M) == A * f(2 * M) + B == A * B * (A + 1) + B == B * (A^2 + A + 1)    (mod M)
...
f(p * M) == B * (A^(p-1) + A^(p-2) + .. + 1)    (mod M)

Function A^p mod M is periodic by p with period being divisor of M, so we can easily calculate f(p * M) in O(M) time by summing up first M items of the sequence above.

Moreover, for this particular problem p (see below) is very small - less than N/M, so we may calculate this sum explicitly.

//////
//3.//
//////

The most pleasant part. Given N, we set p to N / M, and calculate f(p * M) with the method desribed above. N - p * M < M, so all we have to do left is explicitly apply the initial formula N - p * M times to find f(N).

Edited by author 15.02.2006 18:23

Please give me some more tests. And what is the test number 4?

Please, give me some hints and idea. I write bruteForce but i see no hints. Only random 0 and 1.

#include<iostream>
using namespace std;
int main()
{
 int a,b;
cin>>a>>b;
 cout<<a+b;
 return 0;
}