### kazama460's blog

By kazama460, history, 2 months ago, ,

i have been studying mobius inversion from last 1 week , and i have came across this beautiful article on it but i am not able to understand that how eq.3 is transformed into eq.4

Here is the link to the article.

please help me if you can , i have spent a lot of time to understand it.

Thank you.

• -3

By kazama460, history, 14 months ago, ,

i am stuck at simple problem , and the problem is that there is no Editorial available for this problem.

The problem is as follows:

Given M (Distinct) integers A1 , A2 , A3 , A4 , A5 ...... , Am , find all integers K , such that remainder of all elements with k is same I.E. A1%K = A2%K = A3%K = ..... = Am%K

and K>1.

Number of elements are 100 , and Ai <= 10^9

My solution is brute force: i am running a loop from 2 to second largest element (which can be upto 10^9) and finding all k , but its giving TLE.

This is the link to the problem

any hint or help would be appreciative. Thanks in advance and happy coding.

• +2

By kazama460, history, 15 months ago, ,

I am trying to solve a problem on convex hull(my first problem on convex hull) , but don't know why getting WA. I am using Grahm's scan algo to generate all points of Hull , and then simply calculating the parameter of the hull. please can anyone tell me whats wrong with my code. thank you in advance.

Link to my code

• 0

By kazama460, history, 22 months ago, ,
#include<bits/stdc++.h>
using namespace std;

int main()
{
float x1,x2,y1,y2,x3,y3,x4,y4,ansx,ansy;

while(cin>>x1>>y1)
{
cin>>x2>>y2>>x3>>y3>>x4>>y4;

if(x1==x3 && y1==y3)
{
ansx = x2-x1+x4;
ansy = y2-y1+y4;
}

else
if(x2==x3 && y2==y3)
{
ansx = x1-x2+x4;
ansy = y1-y2+y4;
}
else
if(x1==x4 && y1==y4)
{
ansx = x2-x1+x3;
ansy = y2-y1+y3;
}

else
{
ansx = x1-x2+x3;
ansy = y1-y2+y3;
}
printf("%.3lf %.3lf\n", ansx, ansy);
}
}


i dont know whats wrong with code , getting wrong answer. if anyone can point out some problem in the code. thank you in advance. Link to problem

• 0

By kazama460, history, 23 months ago, ,

Hola guys , i have just started learning about graph theory , can somebody give links to some easy questions to practice for the following topics(easy ones please , as i have just started :) )

1-> graph representation(both adjacency matrix and adjacency list). 2-> dfs and bfs.

and your advice are always welcome about how should i progress learning graph theory.

thank you in advance.

• 0

By kazama460, history, 23 months ago, ,

hey there , i was trying to solve UVA problem (UVA 10106 ) and my code seems to work fine for the test cases but dont know why i am getting wrong answer. Link to my code , can anyone point out the problem or a test case for which my code fails. thank you in advance.