# Viral Advertising Hackerrank Problem coderinme

HackerLand Enterprise is adopting a new viral advertising strategy. When they launch a new product, they advertise it to exactly 5 people on social media.

On the first day, half of those 5 people (i.e.,floor(5/2)=2 ) like the advertisement and each person shares it with 3 of their friends; the remaining people (i.e.,5-floor(5/2)=3) delete the advertisement because it doesn’t interest them. So, at the beginning of the second day,floor(5/2) X 3=2 X 3=6 people receive the advertisement.

On the second day, half of the 6 people who received the advertisement share it with 3 new friends. So, at the beginning of the third day, floor(6/2) X 3=3 X 3=9 people receive the advertisement. The diagram below depicts the advertisement’s virality over the first three days (green denotes a person that likes the advertisement and red denotes a person that disliked and deleted it):

Assume that at the beginning of the ith day, people received the advertisement, floor(m/2) people like and share it with 3 new friends, and m-floor(m/2) people dislike and delete it. At the beginning of the (i+1)th day, floor(m/2)X3 people receive the advertisement.

Given an integer, n, find and print the total number of people who liked HackerLand Enterprise’s advertisement during the first n days. It is guaranteed that no two people have any friends in common and, after a person shares the advertisement with a friend, the friend always sees it the next day.

Input Format

A single integer, n, denoting a number of days.

Constraints
1<=n<=50 Output Format Print the number of people who liked the advertisement during the first days. Sample Input 3 Sample Output 9 Explanation This example is depicted by the diagram at the top of the challenge. people liked the advertisement on the first 2day, 3 people liked the advertisement on the second day and 4 people liked the advertisement on the third day, so the answer is 2+3+4=9.

##### I method
```#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int main() {
int n,like,a,v;
cin>>n;
v=6;
a=0;
like=2;

for(int i =2;i<=n;i++)
{

a=floor(v/2);

like+=a;
v=(a)*3;

}
cout<<like<<endl;
return 0;
}

```
##### II Method
``````n = int(input())
shared = 5
total_opened = 0

for _ in range(0, n):
opened = int(shared / 2)
total_opened = total_opened + opened
shared = opened * 3

print(total_opened)``````

### hasectic

A web developer(Front end and Back end), and DBA at csdamu.com. Currently working as Salesforce Developer @ Tech Matrix IT Consulting Private Limited. Check me @about.me/s.saifi