zoj--1067--Color Me Less

#include<iostream>
#include<cmath>
using namespace std;

typedef struct
{
     int R,G,B;
} A;
double D(int G1,int G2,int R1,int R2,int B1,int B2)
{
  return sqrt((double)(G1-G2)*(G1-G2)+(double)(R1-R2)*(R1-R2)+(double)(B1-B2)*(B1-B2));
}

int main()
{
    int i,k,r,g,b;
    A a[18];
    for(i=0;i<16;i++)
       cin>>a[i].R>>a[i].G>>a[i].B;
    while(1)
    {
        cin>>r>>g>>b;
        if(r==-1&&g==-1&&b==-1)
           break;
        double min=D(a[0].G,g,a[0].R,r,a[0].B,b);
        k=0;
        for(i=1;i<16;i++)
        {
            double m=D(a[i].G,g,a[i].R,r,a[i].B,b);
            if(m<min)
            {
               min=m; k=i;
            }
        }
        cout<<"("<<r<<","<<g<<","<<b<<")"<<" maps to ";
        cout<<"("<<a[k].R<<","<<a[k].G<<","<<a[k].B<<")"<<endl;
    }
  return 0;
}