[模拟退火][UVA10228] A Star not a Tree?

#include<bits/stdc++.h>
using namespace std;
inline int read(){
    int ans=0,f=1;char chr=getchar();
    while(!isdigit(chr)){if(chr==‘-‘)f=-1;chr=getchar();}
    while(isdigit(chr)) {ans=(ans<<3)+(ans<<1)+chr-48;chr=getchar();}
    return ans*f;
}
int x[1005],y[1005],n;
double ansx,ansy,ans;
const double delta=0.998;
inline double DIS(double x1,double x2,double y1,double y2){return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));}
//欧几里得距离 
inline double Get_Ans(double a,double b){double ans=0;for(int i=1;i<=n;i++)ans+=DIS(x[i],a,y[i],b);return ans;}
//当前坐标答案 
inline void Fire(){//退火板子 
    double T=19260 /*817*/ ,fx=ansx,fy=ansy;
    while(T>1e-8){
        double tx=T*(rand()*2-RAND_MAX)+fx;
        double ty=T*(rand()*2-RAND_MAX)+fy;//这里调参，乱调就好了（脸白的无所畏惧），但是前面的随机数一定要能够取到负值啊（虽然我没试过不取会不会炸） 
        double tans=Get_Ans(tx,ty);
        double DE=tans-ans;
        if(DE<0)ans=tans,fx=ansx=tx,fy=ansy=ty;
        else if(exp(-DE/T)*RAND_MAX>rand()) fx=tx,fy=ty;
        T*=delta;
    }
}
int main(){
    int T=read();
    while(T--){
        n=read();
        for(int i=1;i<=n;i++)    x[i]=read(),y[i]=read();
        ansx=ansy=0;ans=Get_Ans(0,0);
        for(int i=1;i<=10;i++)    Fire();
        cout<<(int)(ans+0.5);
        if(T) puts("");puts("");
    }
    return 0;
}