Uva--152 (检索，距离计算)

2014-06-03 00:03:22

题意＆思路：计算距离＆检索，不多说。

 

#include <cstdio>
#include <cmath>
#include <iostream>
using namespace std;
const int maxn = 5000;
const double INF = 1000000;
const double eps = 1e-8;

struct Tree{
    double x,y,z;
};

Tree t[maxn + 5];

double Dis(double x1,double y1,double z1,double x2,double y2,double z2){
    double x = x2 - x1;
    double y = y2 - y1;
    double z = z2 - z1;
    return sqrt(x * x + y * y + z * z);
}

int main(){
    int cnt = 0;
    int his[10] = {0};
    double tx,ty,tz;
    while(scanf("%lf %lf %lf",&tx,&ty,&tz) == 3){
        if(tx == 0 && ty == 0 && tz == 0)
            break;
        t[cnt].x = tx;
        t[cnt].y = ty;
        t[cnt].z = tz;
        ++cnt;
    }
    for(int i = 0; i < cnt; ++i){
        double tmin = INF;
        for(int j = 0; j < cnt; ++j){
            if(i == j)
                continue;
            tmin = min(tmin,Dis(t[i].x,t[i].y,t[i].z,t[j].x,t[j].y,t[j].z));
        }
        //因为tmin不为负，所以用(int)向下取整即可，没必要用floor()
        if(10 - tmin > eps)
            ++his[(int)(tmin)];
    }
    for(int i = 0; i < 10; ++i){
        printf("%4d",his[i]);
    }
    puts("");
    return 0;
}