## 138 - Street Numbers

All about problems in Volume 1. If there is a thread about your problem, please use it. If not, create one with its number in the subject.

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x140l31
Learning poster
Posts: 69
Joined: Tue Jan 30, 2007 12:51 am

### Re: problem no 138--help pls

WAandAC wrote:Hi,

I think this is an easy problem, but why i get wa?
Here is my output

Code: Select all

``````         6         8
35        49
204       288
1189      1681
6930      9800
256    131072
7742    131528
11707    132113
19813    134033
25162    135816
``````
Can anyone help me? Thank you!
this output is wrong!

WillWin
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Posts: 4
Joined: Sun Jul 29, 2007 3:41 pm
Location: Taiwan
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### Re: problem no 138--help pls

Code: Select all

``````#include <iostream>
using namespace std;
int main ()
{
int l1 [10] = {6, 35, 204, 1189, 6930, 256, 7742, 11707, 19813, 25162};
int l2 [10] = {8 ,49, 288, 1681, 9800, 131072, 131528, 132113, 134033, 135816};
for ( int i = 0; i < 10; i++)
{
printf ("%10d%10d\n", l1[i], l2[i]);
}
return 0;
}
``````
do operation and compute in long long int type, and get correct answer

hasib_bd
New poster
Posts: 14
Joined: Wed Apr 30, 2008 12:39 pm

### Re: problem no 138--help pls

I think its not illegal to disclose the last pair :

Code: Select all

``  46611179  65918161``
Hope it will help to debug your code and guess the range.

rafastv
New poster
Posts: 22
Joined: Tue Jun 19, 2007 3:18 am

### Re: 138 - Street Numbers

Hi, some tips for you:

1) This is a non-linear diophantine equation, a Pell's equation, there is many methods to solve this kind of equation. Search one, implement it and enjoy. (There is not a general method for non-linear diophantine equations.)

I recommend reading B. Sury's paper: http://www.isibang.ac.in/~sury/chakravala.pdf

2) Use long types from the start for whichever method you use.