# UEMP01 - Editorial

Contest

Probelm Code : UEMP01

Panel Members

Problem Setter:Sintu Kumar

Problem Tester:Sintu Kumar

DIFFICULTY:

EASY

PREREQUISITES:

Sample,Input Processing , Basic Mathematics

PROBLEM:

A cab owner have N number of cars all are running in city. He give a problem to his one employee.
Cab owner want to check whether a user can book a car or not which is inside or on circle of radious K meter.
If User is at origin position (0,0). N cars position are given in (Xi,Yi) formate. Where 1<=i<=N .
If car can be booked give output as “Available” otherwise “Not Available” .
At that time employee is busy to solve other problem. Can you help him to solve this problem.

EXPLANATION:

This is a sample problem you have to find out whether any point lie inside or on the circle of radius k meter. Here user will be always on origin i.e. (0,0) so center of circle will be origin(0,0).

So, Equation of Circle having radius k will be x^2 + y^2 = k^2 .

Lets (Xi,Yi) be position of ith car so if point (Xi,Yi) lie inside or on circle of radius k than it must satisfy the following equation : Xi^2 + Yi^2 <= k^2 .

for any car position(Xi,Yi) of above n cars above equation satisfy than user can book car.Otherwise not be able to book car.

Basic C++ Code:

int main() {

int t;

cin>>t;

while(t–){

`````` int n,k;

cin>>n;

cin>>k;

bool isPossibleBookCab=false;

for(int i=1;i<=n;i++){

int x,y;

cin>>x>>y;

if((x*x + y*y)<=k*k){

isPossibleBookCab=true;

}

}
``````

if(isPossibleBookCab)

``````  cout<<"Available"<<endl;
``````

else

`````` cout<<"Not Available"<<endl;
``````

}

return 0;

}

TIME COMPLEXITY

O(N)

SPACE COMPLEXITY

O(N)

If we are using long long int instead of int then why is it showing wrong answer.