[2016-04-01] [Codeforces] [659D] [Bicycle Race]

• Time: 2016-04-01-19:10:24
• Title Number: [2016-04-01][codeforces][659d][bicycle Race]
• The main topic: walking around the coastline, each walk the way up and down, and finally back to the end, in the corner if not in time to turn will fall into the water, ask how many places may fall into the water
• Analysis:
  • It can be found that in the internal angle of the 270° is possible to fall into the water, set such a place has x, then the inner angle and the n-2 * (* * *) = * x + (n-x) * 90, get x = n? 4 2 n ? 4 2

  
 

   
  

  
#include <cstdio>
   
  

  
using namespace std;
   
  

  
int main(){
   
  

  
 int n;
   
  

  
 scanf("%d",&n);
   
  

  
 printf("%d\n",(n - 4)/2);
   
  

  
 return 0;
   
  

  
}
  
 

From for notes (Wiz)

[2016-04-01] [Codeforces] [659D] [Bicycle Race]