My approach divides into 2 cases

I) A>= sqrt(N) or B>=sqrt(N)
  this can be solved by brute force in O(sqrt(N))

II) A<sqrt(N) and B<sqrt(N)
  now this is more interesting
  in case of gcd(A,B)=1
  you can proof that there exist x,y>=0 that A*x+B*y = N
    since A*x congruent to N (mod B) -> x = N*inv(A,B) % B
    hence 0<=x<=B-1 but B<sqrt(N) and A<sqrt(N)
    then A*x < N so y >= 0
  in case of gcd(A,B)>1
    that's your work!

:)

My program answer true for input from example(for big number too), but i get "Wrong answer" on test 1.

#include <stdio.h>
#include <math.h>
#define N 1000000
int main(int argc, char **argv)
{
    long long int array[N];
    int i=0;
    while (scanf("%Ld", &array[i])>0) {
        i++;
    }
    for(i-=1;i>=0;i--)
        printf("%.4f\n", sqrt(array[i]));
    return 0;
}

I don't think problem statement is clear.. and obviously algorithm difficult is far not worth than 10000+ reading comprehension is possible

Edited by author 16.10.2016 11:24

Don't use scanf !!!!!!

Edited by author 16.10.2016 18:23

For 2 4 it should be days 2 and 4.
For 100 200 it shoould be 100, 102...148(count must be 25 already)...200(count is 51).

I used the formulas with phi and solved a system of 2 equations to get the coefficients, in python using floats.

Any hint why I get WA8? all tests on the forum work.

Hello! Why I got WA?
I can't understand :| IMO this must work... Tnx all.
----------------------------------------------------
dayTotal = (LastDay - FirstDay) + 1;
   for(counter = 1; counter <= dayTotal; counter++)
      {
    n = counter % 2;
    if(n != 0)
       fuse++;
    }
-----------------------------------------------------

I think it takes first player 5 turns to get '*', and 3 turns to move outside,it is at least 8 turns. why is 5 turns?

Wrote on Pascal:

var
  i, j: integer;
  ms, a, b: integer;
  arrg: array of integer;
begin
  Read(ms);
  SetLength(arrg, ms);

  for i := 0 to arrg.Length - 1 do begin
    var temp: integer;
    Read(temp);
    arrg[i] := temp;
  end;

  for j := 1 to arrg.Length - 1 do
    for i := 1 to arrg.Length - j do
      if arrg[i - 1] > arrg[i] then
        Swap(arrg[i - 1], arrg[i]);

  a := arrg.Length div 2;

  for i := 0 to a do
    b := b + arrg[i] div 2 + 1;

  Write(b);
end.

Wrong answer ( test 1 ).

        long ans[] = new long[23];
        ans[2]=lim[2];
        for (int i=4; i<=20; i+=4) {
            int half=i/2;
            ans[i]=lim[half]*lim[half];
            ans[i+2]=lim[half]*lim[half+2];
        }
        System.out.println(ans[N]);

Как узнать заранее, сколько выделять ячеек для решета?

#include <bits/stdc++.h>
using namespace std;
const int N = 112345;
int a[N];
int b[N];

main()
{
    string s, t;
    cin >> s;
    int cnt = 0;
    int mx=0;
    int l=0;
int cnte=0;
    for(int i = s.size() - 1; i >= 0; i --)
    {
        t = s[i] + t;
        a[0] = 0;

        for(int j = 1; j < t.size(); j ++)
        {
            int x = a[j - 1];
            while(x > 0 && t[x] != t[j])
                x = a[x - 1];
            if(t[x] == t[j])
                x ++;
            a[j] = x;
            mx = max(mx, a[j]);

        }
            b[i]=mx;
            if(mx==0)cnte++;
            mx=0;

    }
    if(cnte==s.size()){cout<<s;return 0;}
    else
for(int i=0;i<s.size();i++){if(b[i]>=1)cout<<s[i];}


}
// any suggestion guys I have no idea what can be  the fifth test thanks in advance

6 2
2 10 11 16 16 21
32
33

Can you give me a test for wa 7, please?

import sys
import math
string = sys.stdin.read()
def string_parsing(string):
    result = []
    str = ''
    for j in range(len(string)):
        if string[j] != ' ' and string[j] != '\n':
            str += string[j]
        elif str !='':
            result.append(str)
            str = ''
    return result

list = string_parsing(string)
list = [round(math.sqrt(float(elem)), 5) for elem in list]
list = ["{0:.5f}".format(elem) for elem in list]
for i in range(len(list)):
    sys.stdout.write(str(list.pop()) + '\n')

#What's wrong?



Edited by author 12.10.2016 16:17

6
0 0
5 -10
10 -10
5 -5
10 -5
20 0

7
1 2 10
2 3 30
3 5 20
5 4 20
4 2 20
3 6 10
1 6 7

ans:
17
1 2 10
2 3 30
3 5 20
5 4 20
4 2 20
3 6 10
1 6 7

Is this output acceptable? Or do we have to remove flow cycles?

update: got ac without removing cycles.

Edited by author 13.10.2016 06:41

What is in test 4?
I have WA and I dont know what is wrong.

I did it! I have TL 15 for a long time, but now I solved the problem. I use treap with gcd, but treap has a big constant and gcd works for O(log), so I write binary algorithm of calculating gcd instead of Euclid and it works!

hello,i got wa3.can you tell me why?or give me some tests.thank you very much!
the source:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;


namespace Timus1003
{
    class Program
    {
        static void Main(string[] args)
        {
            System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture;
            List<Phone> arrayList=new List<Phone>();
            while(true)
            {


                string phoneNumber=Console.ReadLine();
                if(phoneNumber=="-1")
                {
                    break;
                }
                Phone phone = new Phone();
                phone.PhoneNumber =phoneNumber ;
                phone.Size =Convert.ToInt32(Console.ReadLine());
                string[] dics = new string[phone.Size];
                int n=0;
                while(n<phone.Size)
                {
                    dics[n] = Console.ReadLine();
                    n++;
                }
                phone.Dics = dics;
                arrayList.Add(phone);
            }
    //        Console.WriteLine("out");
            for(int i=0;i<arrayList.Count;i++)
            {

                Phone phone = arrayList[i];
                phone.Dics = phone.Dics.OrderByDescending(s => s.Length).ToArray<string>();
                String[] str = new String[phone.Dics.Length];
                for(int j=0;j<phone.Dics.Length;j++)
                {
                    str[j] = wordToNumber(phone.Dics[j]);
                }
                phone.HasSolution=find(phone.PhoneNumber, str, phone);
                if(phone.HasSolution)
                {
                    string solutionStr = "";
                    for(int k=0;k<phone.Solutions.Count;k++)
                    {
                        if(k==phone.Solutions.Count-1)
                        {
                            solutionStr = solutionStr + phone.Solutions[k] + "";
                        }
                        else
                        {
                            solutionStr = solutionStr + phone.Solutions[k] + " ";
                        }

                    }

                    Console.WriteLine(solutionStr);
                }
                else
                {
                    Console.WriteLine("No solution.");
                }
            }

            Console.ReadLine();


        }

        public static bool find(string phoneNumber,string[] dics,Phone phone)
        {

            for (int i = 0; i < dics.Length;i++ )
            {

          //      if (phoneNumber == "") return true;
                if (phoneNumber == dics[i])
                {
                    phone.Solutions.Add(phone.Dics[i]);
                    //Console.Write(phone.Dics[i] + " ");
                    return true;
                }

                if (phoneNumber.IndexOf(dics[i]) == 0)
                {
                    phone.Solutions.Add(phone.Dics[i]);
                   // Console.Write(phone.Dics[i] + " ");
                    string newPhoneNumber = phoneNumber.Substring(dics[i].Length);
                    if(find(newPhoneNumber, dics, phone))
                    {
                        return true;
                    }
                    else
                    {
                        phone.Solutions.RemoveAt(phone.Solutions.Count-1);
                        continue;
                    }

                }


            }
         //   Console.WriteLine("No solution.");
            return false;
        }


        public static string wordToNumber(string word)
        {
            char[] wordArr = word.ToCharArray();
            char[] numArr = new char[wordArr.Length];
            for (int i = 0; i < wordArr.Length;i++ )
            {
                numArr[i] = charToNumber(wordArr[i]);
            }
            return new String(numArr);
        }

        public static char charToNumber(char mychar)
        {
            switch(mychar)
            {
                case 'i':
                case 'j':
                    return '1';
                case 'a':
                case 'b':
                case 'c':
                    return '2';
                case 'd':
                case 'e':
                case 'f':
                    return '3';
                case 'g':
                case 'h':
                    return '4';
                case 'k':
                case 'l':
                    return '5';
                case 'm':
                case 'n':
                    return '6';
                case 'p':
                case 'r':
                case 's':
                    return '7';
                case 't':
                case 'u':
                case 'v':
                    return '8';
                case 'w':
                case 'x':
                case 'y':
                    return '9';
                case 'o':
                case 'q':
                case 'z':
                    return '0';
                default:
                    return mychar;
            }

        }
    }

    class Phone
    {
        string phoneNumber;

        public string PhoneNumber
        {
            get { return phoneNumber; }
            set { phoneNumber = value; }
        }
        int size;

        public int Size
        {
            get { return size; }
            set { size = value; }
        }
        string[] dics;

        public string[] Dics
        {
            get { return dics; }
            set { dics = value; }
        }

        List<string> solutions = new List<string>();

        public List<string> Solutions
        {
            get { return solutions; }
            set { solutions = value; }
        }

        bool hasSolution;

        public bool HasSolution
        {
            get { return hasSolution; }
            set { hasSolution = value; }
        }

    }
}

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

int main()
{
    double len=0;
    int n,r,i,j;
    scanf("%d %d",&n,&r);
    double a[200][2];
    for(i=0;i<n;i++)
        for(j=0;j<2;j++)
            scanf("%lf",&a[i][j]);
    for(i=1;i<n;i++)
        len=len+sqrt((a[i][1]-a[i-1][1])*(a[i][1]-a[i-1][1])+(a[i][0]-a[i-1][0])*(a[i][0]-a[i-1][0]));
    len=len+sqrt((a[i-1][1]-a[0][1])*(a[i-1][1]-a[0][1])+(a[i-1][0]-a[0][0])*(a[i-1][0]-a[0][0]));
    len=len+3.141*2*r;
    printf("%.2lf",len);
    fflush(stdin);
    getchar();
    return 0;
}