Problem:
Score : 100 points

Problem Statement

Takahashi wants to print a document with N pages double-sided, where two pages of data can be printed on one sheet of paper.

At least how many sheets of paper does he need?

Constraints

N is an integer.

1 \leq N \leq 100

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

5

Sample Output 1

3

By printing the 1-st, 2-nd pages on the 1-st sheet, 3-rd and 4-th pages on the 2-nd sheet, and 5-th page on the 3-rd sheet, we can print all the data on 3 sheets of paper.

Sample Input 2

2

Sample Output 2

1

Sample Input 3

100

Sample Output 3

50

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
 
int main() {
  
  bool bingo = false;

  vector<vector<int>> sheet(3,vector<int>(3));

  for(int i=0;i<3;i++){
    for(int j=0;j<3;j++){
      cin>>sheet.at(i).at(j);
    }
  }//シートの入力

  int N,judge;
  vector<int> ans(N);

  cin>>N;

  for(int i=0;i<N;i++){
    cin>>ans.at(i);
  }//抽選番号の入力


  for(int i=0;i<N;i++){
    for(int j=0;j<3;j++){
      for(int k=0;k<3;k++){
        if(sheet.at(j).at(k)==ans.at(i)){
          sheet.at(j).at(k)=0;
        }
      }
    }
  }//あたり数を0に置き換え
 

  if(!(sheet.at(0).at(0)&&sheet.at(0).at(1)&&sheet.at(0).at(2))){
    bingo=true;
  }
  
  if(!(sheet.at(1).at(0)&&sheet.at(1).at(1)&&sheet.at(1).at(2))){
    bingo=true;
  }

  if(!(sheet.at(2).at(0)&&sheet.at(2).at(1)&&sheet.at(2).at(2))){
    bingo=true;
  }

  if(!(sheet.at(0).at(0)&&sheet.at(1).at(0)&&sheet.at(2).at(0))){
    bingo=true;
  }

  if(!(sheet.at(0).at(1)&&sheet.at(1).at(1)&&sheet.at(2).at(1))){
    bingo=true;
  }

  if(!(sheet.at(0).at(2)&&sheet.at(1).at(2)&&sheet.at(2).at(2))){
    bingo=true;
  }

  if(!(sheet.at(0).at(0)&&sheet.at(0).at(1)&&sheet.at(0).at(2))){
    bingo=true;
  }

  if(!(sheet.at(0).at(0)&&sheet.at(1).at(1)&&sheet.at(2).at(2))){
    bingo=true;
  }

  if(!(sheet.at(0).at(2)&&sheet.at(1).at(1)&&sheet.at(2).at(0))){
    bingo=true;
  }


  
  if(bingo==true){
      cout<<"Yes"<<endl;      
  }
  else{
      cout<<"No"<<endl;      
  }//答えの出力




}