UVA152-Tree's a Crowd

题意：求各棵树到其他树的最短距离，然后记录下来，距离只有0-9

思路：暴力把。。。直接搜索，但要记住，最后的距离是向下取整，而不是向上取整，刚开始理解错误，用ceil取整距离，WA了好多次，后来才发现，直接用int强制转化

#include<stdio.h> 
#include<stdlib.h>
#include<math.h> 
#include<string.h>

int dis[11];

struct space{
	double x, y, z;
}space[5050];

double lenth(double a, double b, double c, double d, double e, double f){
	double l;
	return l = sqrt((a - d) * (a - d) + (b - e) * (b - e) + (c - f) * (c - f));
}

int main(){
	int cnt = 0, min;	
	double L;	
	memset(dis, 0, sizeof(dis));	
	while (scanf("%lf%lf%lf", &space[cnt].x, &space[cnt].y, &space[cnt].z)){
		if (!space[cnt].x && !space[cnt].y && !space[cnt].z)	
			break;
		cnt++;	
	}
	for(int i = 0; i < cnt; i++){
		min = 9999999;	
		for(int j = 0; j < cnt; j++){
			if (i == j)	
				continue;		
			L = lenth(space[i].x, space[i].y, space[i].z, space[j].x, space[j].y, space[j].z);		
			if (L < min)				
				min = L;			
			}
		if (min <= 9){
			int k = floor(min);	
			dis[k]++;
		}
	}	
			
	for(int i = 0; i < 10; i++)	
		printf("%4d", dis[i]);
		printf("\n");	
	return 0;
}