30 lines
753 B
C++
30 lines
753 B
C++
#include<stdio.h>
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#include<math.h>
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struct p{
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double x,y;
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};
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double cross(p a,p b,p c){
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return (b.x-a.x)*(c.y-a.y)-(c.x-a.x)*(b.y-a.y);
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}
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int main(){
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int t;
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scanf("%d",&t);
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while(t--){
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int n;
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p p1,p2,tp;
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double res=0,s,tx=0,ty=0;
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scanf("%d",&n);
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scanf("%lf%lf%lf%lf",&p1.x,&p1.y,&p2.x,&p2.y);
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for(int i=3;i<=n;++i){
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scanf("%lf%lf",&tp.x,&tp.y);
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s=cross(p1,p2,tp);
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res+=s;
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tx+=(p1.x+p2.x+tp.x)*s;
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ty+=(p1.y+p2.y+tp.y)*s;
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p2.x=tp.x;p2.y=tp.y;
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}
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printf("%.2lf %.2lf\n",tx/(3*res),ty/(3*res));
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}
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return 0;
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}
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