toj_2920.cpp

Tianjin University Online Judge 的80多道题目 .

/*2920.   Help Hakim Time Limit: 3.0 Seconds   Memory Limit: 65536K
Total Runs: 13   Accepted Runs: 4
Case Time Limit: 1.0 Seconds


06 batch of CUET (Chittagong University of Extra Talent) has solved the previous problem of fruit seller Hakim. He only knows to stack fruits in a single layer. He is grateful to the programmer of 06 batch.

Fig: Level 3 Stack

Now he is in another trouble. He wants to stack fruits in 3D fashion. That means each fruit contain three fruits support under it. At the top level only exist one fruit and at the 2nd level from top there should be three fruits and the next levels from the top to bottom follow the same rule. He wants calculate the number of fruits require for N level stack. Who can help him!!!!!
Input

Each line of input set will contain a single integer N where 0≤N≤106.
Output

Output will contain the total number of fruits required for N level.
Sample Input

1
2
3

Sample Output

1
4
10

Problem Setter: MD. Nazmul Kibria
Problem Idea: MD. Omar Faruque


Source: CUET individual contest*/
#include<cstdio>
int main()
{
  long long n , temp , result;
  while ( scanf( "%lld" , &n ) != EOF )
    {
      temp = n * ( n + 1 ) / 2;
      result = (temp * ( 2 * n + 1 ) / 3 + temp ) / 2;
      printf( "%lld\n", result );
    }
  return 0;
}