1020.cpp

来自「我的URAL的1000 ~ 1050 的全部代码 包含WA 最后AC的程序 有2」· C++ 代码 · 共 45 行

#include <iostream>
#include <math.h>
using namespace std;

const int maxN = 100;
const double PI = 3.1415926;
int n;
double ans,r;
struct point{ double x,y; };

point pArr[ maxN + 1 ];
double dis( point a, point b )
{
	return sqrt( (a.x - b.x)*(a.x - b.x) + (a.y - b.y)*(a.y - b.y) );
}

void readIn()
{
	int i;
	cin >> n >> r;

	for( i = 1; i <= n; i++ )
		{ cin >> pArr[i].x >> pArr[i].y; }
}

void work()
{
	int i;
	for( i = 1; i < n; i++ )
		ans += dis( pArr[i],pArr[i+1] );
	ans += dis( pArr[i],pArr[1] );
	ans += 2*PI*r;
}
int main()
{
//	freopen("1020.in","r",stdin);
	readIn();
	work();
	cout.setf(ios::fixed);
	cout.precision(2);
	cout << ans << endl;
	return 0;
}