using System;
using static System.Console;

public static class prernd {

public static vector randomvec(vector a,vector b,Random rnd){
	vector x=new vector(a.size);
	for(int i=0;i<a.size;i++)x[i]=a[i]+(b[i]-a[i])*rnd.NextDouble();
	return x;
	}

public static vector run
(Func<vector,double>f,vector a,vector b,int seconds=1,double acc=1e-3,int N=100){
	var rnd = new Random();
	vector best=(a+b)/2;
	double fbest=f(best);
	var start_time=DateTime.Now;
	do{
		for(int i=0;i<N;i++){
			vector x=randomvec(a,b,rnd);
			double fx=f(x);
			if(fx<fbest){
				best=x;
				fbest=fx;
			}
		}
	}while((DateTime.Now-start_time).TotalSeconds < seconds);
	qnewton.min(f,ref best,acc:acc);	
	return best;
}

}//class