模拟退火法模板

#include"string.h"
#include"stdio.h"
#include"iostream"
#include"queue"
#include"stack"
#define M 10009
#define N 100009
#include"stdlib.h"
#include"math.h"
#define inf 99999999
#define eps 1e-8
#define PI acos(-1.0)
using namespace std;
struct node
{
    double x,y,dis;
}p[6],q[100];
double max(double x,double y)
{
    return x>y?x:y;
}
double min(double x,double y)
{
    return x<y?x:y;
}
double len(node a,node b)
{
    return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
}
double fun(node q)
{
    double sum=0;
    for(int i=0;i<4;i++)
        sum+=len(q,p[i]);
    return sum;
}
int main()
{
    int i,j;
    while(scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&p[0].x,&p[0].y,&p[1].x,&p[1].y,&p[2].x,&p[2].y,&p[3].x,&p[3].y)!=-1)
    {
        int flag=0;
        for(i=0;i<4;i++)
            if(fabs(p[i].x+1)<eps&&fabs(p[i].y+1)<eps)
            flag++;
        if(flag==4)
            break;
        node a,b;
        a.x=a.y=inf;
        b.x=b.y=-inf;
        for(i=0;i<4;i++)
        {
            a.x=min(a.x,p[i].x);
            a.y=min(a.y,p[i].y);
            b.x=max(b.x,p[i].x);
            b.y=max(b.y,p[i].y);
        }
        for(i=1;i<=20;i++)//枚举的时候尽量在内部枚举这些点
        {
            q[i].x=(rand()%1000+10)/1000.0*(b.x-a.x)+a.x;//
            q[i].y=(rand()%1000+10)/1000.0*(b.y-a.y)+a.y;//
            q[i].dis=fun(q[i]);
        }
        double temp=len(a,b);
        while(temp>eps)
        {
            for(i=1;i<=20;i++)
            {
                for(j=0;j<25;j++)
                {
                    double rad=(rand()%1000+10)/1000.0*PI*10;
                    node cur;
                    cur.x=temp*cos(rad);
                    cur.y=temp*sin(rad);
                    if(cur.x<a.x||cur.y<a.y||cur.x>b.x||cur.x>b.y)continue;
                    cur.dis=fun(cur);
                    if(cur.dis<q[i].dis)
                        q[i]=cur;
                }
            }
            temp*=0.981;
        }
        double mini=q[1].dis;
        for(i=2;i<=20;i++)
        {
            if(mini>q[i].dis)
                mini=q[i].dis;
        }
        printf("%.4lf
",mini);
    }
}