i don't understand why. maybe somebody could help...
here's the code

from math import sqrt
n=int(input())
l=0
a=[None]*n
b=[None]*n
for k in range(n):
    a[k]=int(input())
for z in range(n):
    p=0
    for i in range(n):
        if a[i]>p:
            p=a[i]
            l=i
    b[z]=n-1-l
    a[l]=-a[l]
for z in range(n):
    a[z]=-a[z]
while n>1:
     n=n-1
     a[b.index(n-1)]=2*sqrt(a[b.index(n)]*a[b.index(n-1)])
print('{:.2f}'.format(a[b[0]]))

Edited by author 27.10.2020 23:40

Hello. How can I find the input values for Test 7? It says that I have a wrong answer there.

Use the priority queue data structure.

Приятно было прикоснуться к наследию легендарного человека

Я знаю,  что здесь еще есть от него задача Currency Exchange

I got AC on this simply by guessing that combining the stripies from the largest down to the smallest would result in the smallest colony size. Can someone explain what mathematical or logical reasoning would be used to arrive at this conclusion, or prove that this conclusion would be true?

good problem!

But you can't, so here is a meaningless post. Originally it was about not understanding the sample because for some reason I thought there were four stripies, one of them weight 3. I sat for 20 minutes trying to figure out why the sample was correct. :)

Edited by author 29.06.2013 16:13

Did you use DP to solve this problem?
How did you do it?

I am getting WA for test#15 with my C++ code. Is there anybody who can give an explanation why this is happening?

If you got WA #3, check case n=1 ;)

I've read it for 15 min..AC at the first time...
sort all the integer to a descending sequence.
repeat for n-1 times:
combine a[1] and a[2](2sqrt(xy))
delete(a[1],a[2])
insert the new real number into the sequence
and remember to keep the descending.

print the final a[1].

Don't use any collections (TreeSet/HashSet/etc) (ArrayList might also be a problem)

looks like when they add/remove/update their elements they do some stuff to their elements, so that doubles change their magnitude.

u might also try to use YouOwnDouble class implements Comparable

input:
3
72
30
50

output:
120.00

But the task is to find the minimal weight!
I wonder how 120.00 (2*sqrt(72*50)) can be minimal? It's maximal!

please tell me:admins,What is WA7?

Can anyone tell me the input for test 1 and test 3?
My code works correctly on my system but i keep getting WA.

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


#define NUM 100

// stripes # 1161
int main()
{
   int num;
   int weight[NUM];
   int i;
   int j;
  static  int k = 0;
   float coll[NUM];
   float temp;

    scanf("%d",&num);  // number of stripes

    for ( i = 0 ; i <= num ; i++)
    {
       if ( i == num) weight[i] = 1;  // end of the array
       else
       scanf("%d",&weight[i]);   // input the weight of the stripes
     } // end of for loop

     for ( i = 0 ; i < num-1 ; i++)
     {
       for  ( j = i+1 ; j < num; j++)
       {
        coll[k] = 2 * sqrt( weight[i] * weight[j]);  // calculate the collision weights
        k++;
       }
    }

/*for ( i = 0 ; i < k ; i++)
{
  printf("\n%f",coll[i]);
 }*/

   for(i=0 ; i < num; i++)   // sort the array
  {
     for ( j = i+1 ; j <= num ; j++)
     {
        if (coll[i] > coll[j] )
        {
           temp = coll[i];
           coll[i] = coll[j];
           coll[j] = temp;
         } //  end of if
   }  // end of j for loop
   }  // end of i for loop

/*for ( i = 0 ; i < k ; i++)
 {
     printf("\n%.2f\n", coll[i]);
  } */

   printf("\n\n%.2f\n",coll[0]);  // print the least value
     return 0;

     } // end of main


Sometimes the array is not getting sorted
can anyone tell me why?

Help needed.....

can you please help me about what is wrong about this?



You tried to solve problem 1161 Stripies.
Your solution was compiled with the following errors:

93e006e3-949c-4a74-a88f-eb4b2c6dc082
93e006e3-949c-4a74-a88f-eb4b2c6dc082(19): error: expression must have a constant value
int set[N];
^

/* why can't I declare a new array like this? (N is integer) */

93e006e3-949c-4a74-a88f-eb4b2c6dc082(61): error: expression must have a constant value
int aux[max-min+1], i=min, k=0;
^

/* The same */

93e006e3-949c-4a74-a88f-eb4b2c6dc082(61): error: expression must have a constant value
int aux[max-min+1], i=min, k=0;
^

/* Two errors on the same line!!! */

compilation aborted for 93e006e3-949c-4a74-a88f-eb4b2c6dc082 (code 2)

Is there any1 could give me some noticeable points about this test???
I try both accuracy of 2 and 3 decimal digits after the point but in both cases I got Wrong at test # 15.

I put Solution=2*(sqrt(Solution*array[i])) i from n-1 downto 1(I omit same numbers before and my array is sorted in increasing order ).

I DONT KNOW WY MY PROGRAM ISN'T CORECT
HERE IS MY CODE. WHY WA??

[code deleted]

Edited by moderator 09.05.2007 16:03