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 (Clang 3.8.0) (judge verdict: Wrong Answer)

#include<iostream>
#include<algorithm>
#include<cmath>
#include<vector>
#include<map>
#include<set>
#include<string>

#define fast_io ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

using namespace std;

//inline int read(){int t = 0;int neg=1;char c;while((c=getchar_unlocked())!='\n'&&c!=' '&&c!=EOF){if(c=='-'){neg=-1;continue;}t=t*10+c-48;}return neg*t;}
//inline int readl(){long long t = 0;long long neg=1ll;char c;while((c=getchar_unlocked())!='\n'&&c!=' '&&c!=EOF){if(c=='-'){neg=-1ll;continue;}t=t*10+c-48;}return neg*t;}

#define debug(x) cout<<(#x)<<"="<<(x)<<", ";
#define debug1(x) debug(x) cout<<'\n';
#define debug2(x1, x2) debug(x1) debug(x2) cout<<'\n';
#define debug3(x1, x2, x3) debug(x1) debug(x2) debug(x3) cout<<'\n';
#define debug4(x1, x2, x3, x4) debug(x1) debug(x2) debug(x3) debug(x4) cout<<'\n';
#define debug5(x1, x2, x3, x4, x5) debug(x1) debug(x2) debug(x3) debug(x4) debug(x5) cout<<'\n';

typedef long long int lli;
typedef unsigned long long int ulli;
typedef pair<int,int> pi;
typedef pair<lli,lli> plli;
typedef vector<int> vi;
typedef vector<lli> vlli;
typedef vector<pi> vpi;
typedef vector<plli> vplli;
const lli M=1000000007ll;

int main(){
	fast_io 
	int n;cin>>n;
	cout<<(n/2);
	
	return 0;
}