TOJ 1809.Playground（多角形条件を構成）
テーマリンク:http://acm.tju.edu.cn/toj/showp1809.html
1809.
Playground
Time Limit: 1.0 Seconds
メモリLimit: 65536 K
Total Runs: 3056
Acceepted Runs: 770
George has K≦20 steel wires shaped in the form of half-circles、with radii a
1,a
2,…，a
K.The y can be solded at the ends、in any angle.Is it possible for George to make a closed shop of these wires？He does not have to use all the wires.
The Wires can be combined at any angle，but may not intersect.Beware of float point errors.
Input specification s
Each data set consists of a number 0＜K≦20 on a line by itself、フォローアップby line of K space-separated numbers ai.Each number is in the range 0＜ai < 107,and has at most 3 digits after the decimal point.The input will be terminated by a zero on a line by itself.
Output specification s
For each test case，there shound be one word on a line by itself：「YES」if it is possible to make a simple connected figure out of the given arcs，and「NO」if it isn't.
Sample Input
Submit List Runs Forum Statistics
多角形を構成する条件と同じです。半円に対しては、二つの半円が閉じられます。
1809.
Playground
Time Limit: 1.0 Seconds
メモリLimit: 65536 K
Total Runs: 3056
Acceepted Runs: 770
George has K≦20 steel wires shaped in the form of half-circles、with radii a
1,a
2,…，a
K.The y can be solded at the ends、in any angle.Is it possible for George to make a closed shop of these wires？He does not have to use all the wires.
The Wires can be combined at any angle，but may not intersect.Beware of float point errors.
Input specification s
Each data set consists of a number 0＜K≦20 on a line by itself、フォローアップby line of K space-separated numbers ai.Each number is in the range 0＜ai < 107,and has at most 3 digits after the decimal point.The input will be terminated by a zero on a line by itself.
Output specification s
For each test case，there shound be one word on a line by itself：「YES」if it is possible to make a simple connected figure out of the given arcs，and「NO」if it isn't.
Sample Input
1
4.000
2
1.000 1.000
3
1.455 2.958 4.424
7
1.230 2.577 3.411 2.968 5.301 4.398 6.777
0
NO
YES
NO
YES
Submit List Runs Forum Statistics
多角形を構成する条件と同じです。半円に対しては、二つの半円が閉じられます。
#include
#include
using namespace std;
int main(){
double wire[21];
int n;
while(~scanf("%d",&n),n){
bool flag=false;
for(int i=0;i