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Python 3 WA 5th test | feather | 1161. Stripies | 27 окт 2020 22:24 | 1 |
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 |
Input values of Test 7 | Oybek | 1161. Stripies | 27 дек 2018 19:53 | 2 |
Hello. How can I find the input values for Test 7? It says that I have a wrong answer there. What is your code? Are you using double or float? |
For C++ Users | 0blivium | 1161. Stripies | 9 ноя 2018 03:58 | 1 |
Use the priority queue data structure. |
Легендарный Николай Дуров | Mahilewets | 1161. Stripies | 26 июл 2017 23:54 | 1 |
Приятно было прикоснуться к наследию легендарного человека Я знаю, что здесь еще есть от него задача Currency Exchange |
I guessed - can someone explain why? | Steve | 1161. Stripies | 30 мар 2017 21:34 | 4 |
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? I guessed the same and also I want to know mathematical proof The factor 2 does not matter -- you will always find one 2 which was sqrt'ed (n-1) times, ..., one 2 not sqrt'ed. OOH, there will be exactly two given number which got sqrt'ed (n-1) times, ..., one given number that got sqrt'ed once. Therefore, you will want larger numbers be sqrt'ed more times. Edited by author 22.03.2016 12:08 I can explain Okay, we have sequence m1,m2,m3,m4.... of weights in input But now imagine that we have a heap of stripies with their weights. Our answer (for example n=4) will be: 2*sqrt(m1*2*sqrt(m2*2*sqrt(m3*m4))) for greater understanding write it on a sheet. So we need to maximize it but we don't know order of m1,m2,m3,... which give max answer. It's clear that if 2*sqrt(m1*2*sqrt(m2*2*sqrt(m3*m4))) should be maximum then m1*2*sqrt(m2*2*sqrt(m3*m4)) (in sqrt) should be maximum too. Reasoning in this way we understand that we need m3*m4 be maximum. So this sequence should be sorted in this way: m4>=m3>=m2>=m1 I hope my English is enough to explain it)))) Edited by author 31.03.2017 19:50 |
AC in 4 line without input | [RISE] Levon Oganesyan [RAU] | 1161. Stripies | 12 янв 2016 23:27 | 2 |
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I wish you could delete posts. | Kuros | 1161. Stripies | 2 сен 2014 15:25 | 2 |
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 This post is not meaningless at all. I was sitting, counting stripies weight from the sample with a 3-weight stripie too. So thank you for clarifying! |
DP? | nYz]LL_taO | 1161. Stripies | 22 дек 2013 06:15 | 3 |
DP? nYz]LL_taO 27 сен 2007 12:51 Did you use DP to solve this problem? How did you do it? Re: DP? jagatsastry 19 ноя 2007 01:53 use greedy algo instead. choose the largest numbers for the innermost square roots so that their values get depreciated with each iteration. this is how i did. sort arr in reverse order [code deleted] cur is the final answer Edited by moderator 19.10.2019 19:45 you can use dp in this task, like in the classical task "how to multiply n matrices in optimal way". it's O(n^3), so suitable. also there's greddy algorithm, O(n). |
WA with test#15 | Md. Kamrul Islam | 1161. Stripies | 6 июл 2013 17:16 | 2 |
I am getting WA for test#15 with my C++ code. Is there anybody who can give an explanation why this is happening? Try a to test with two same masses: 5 11 13 21 10000 10000 Then when you will understand what was your problem you will use std::multiset<double, std::greater<double>> s; Cheeres! ;) |
WA #3 | TheDreamCatcher | 1161. Stripies | 26 июн 2013 22:02 | 2 |
WA #3 TheDreamCatcher 14 авг 2011 13:17 If you got WA #3, check case n=1 ;) Re: WA #3 [TDUweAI] daminus 26 июн 2013 22:02 |
GOT ac | yangdong | 1161. Stripies | 27 ноя 2012 18:08 | 4 |
GOT ac yangdong 18 окт 2010 17:52 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]. Re: GOT ac AYUBXON UBAYDULLAYEV (IT of TUIT) 25 май 2012 17:24 what's mean here is delete(a[1],a[2]); don't understand Re: GOT ac Anupam Ghosh, Wipro Technologies 18 окт 2012 20:28 Hi Ayubxon, delete means "no longer worry about a[1] and a[2]". You may not actually delete the values from array. Regards Anupam Re: GOT ac AYUBXON UBAYDULLAYEV TUIT 27 ноя 2012 18:08 |
JAVA WA#15 | ile | 1161. Stripies | 29 окт 2012 02:46 | 2 |
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 using collections gives AC so u r mad |
The sample is incorrect?! | Ilya (Vologda SPU) | 1161. Stripies | 14 окт 2012 15:34 | 3 |
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! Sorry, sample is ok, my thought is not ^^" step #1 : 2*sqrt(72*50) =120 --> colliding 72 and 50 and new stripy with weight 120 step #2 : 2*sqrt(120*30)=120 --> colliding 120 and 30 and new stripy with weight 120 |
admins,What is WA7? | QAFQAZFECE | 1161. Stripies | 15 май 2010 02:14 | 9 |
please tell me:admins,What is WA7? Your programs gives wrong answer on 7th test. But what is the 7yh test.I am working on it till morning.PLease help ,me What is wrong with my programm.in my pc it works correctly. What is wrong with my programm.in my pc it works correctly. When i enter 100 there is error in exe,Why? Why WA#1?I can't understand,my program runs weel in my |
WA | rohit | 1161. Stripies | 26 окт 2009 21:56 | 4 |
WA rohit 29 дек 2007 02:36 Can anyone tell me the input for test 1 and test 3? My code works correctly on my system but i keep getting WA. Re: WA ErOPb|4[USU] 14 мар 2009 03:39 Re: WA Volov_Forever 17 апр 2009 02:00 1 123 What is the answer of this test? Re: WA Ilya (Vologda SPU) 26 окт 2009 21:56 123,00 It means that no stripies collided in this case. |
Could anyone explain the test data? | minkerui | 1161. Stripies | 30 июл 2009 22:58 | 6 |
2*Sqrt(72*50)=60 2*Sqrt(60*120)=120 so answer:120.00 Isn't should be: 2*Sqrt(72*50)=60 2*Sqrt(30*120)=120 I suppose that author of post accidentally wrote 60 instead of 30, but anyway it's understandble Edited by author 16.06.2005 06:34 Isn't should be: 2*sqrt(72*50)=120 2*sqrt(30*120)=120 I suppose that author of post accidentally wrote 60 instead of 120, but anyway it's understandble Understand Edited by author 30.07.2009 23:02 |
Whats wrong with this code? | Sridhar | 1161. Stripies | 15 мар 2009 18:48 | 1 |
#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.....
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COMPILATION ERROR in the Array declaration!!! | Sergio Ligregni | 1161. Stripies | 31 янв 2008 01:26 | 4 |
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) You couldn't declare array with nonconstant value! In this case try to use dynamic array, or vector. int aux = new int[N]; or vector<int> aux(N); Thaks for helping (I didn´t tried yet) But... does C (ANSI C, not C++) accept the "vector" type or "int a = new int[10]"??? I have solved dozens of problems using "int a[x];" at UVa online judge, I think there could be more reasonable to forbid the "vector" type using (not elemental) than "int a[x];" (ANSI C elemental array using) Thanks I hope your reply Sergio Ligregni, MEX Sorry I've made a mistake... Not int aux = new int[N]; should be : int * aux = new int[N]; P.S. I don't know how to be with ANSI C, because I've never use it... P.P.S. I always use vector(or other STL containers). |
Test # 15 | cyanbird | 1161. Stripies | 1 окт 2007 21:56 | 3 |
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 ). Check your code for errors, because I've the same algo and AC!!! First time I solve this problem on C++ with same algo and have WA#15. When I write my code on Pascal I have AC. . . It's strange. . . May be it's problem with precision or type conversion. Edited by author 02.10.2007 00:52 |
WHY WA??????????????? PLEASE HEPL ME!!!! | BAron | 1161. Stripies | 13 май 2007 15:08 | 2 |
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 Wa #5, please hepl! Post some test, please! |