百练4091:最近餐馆

传送门：http://bailian.openjudge.cn/practice/4091

【题解】

这垃圾题还卡常？？？

首先我们发现暴力做是O(nqlogn)的，这个logn是log5000大概12

我们发现可以把它优化到O(nqm)的，m=10，然后就过了。

可能数据不满吧。。

# include 
# include <string.h>
# include 
# include 
// # include 

using namespace std;

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
const int M = 5000 + 10;
const int mod = 1e9+7;

# define RG register
# define ST static

int n, K, m;

int chosen[M];

struct point {
    int a[5];
    ld c;
    friend bool operator <(point a, point b) {
        return a.c<b.c;
    }
}p[M], q;

int main() {
    while(cin >> n >> K) {
        memset(chosen, 0, sizeof chosen);
        for (int i=1; i<=n; ++i) 
            for (int j=0; j"%d", &p[i].a[j]);
        int Q; cin >> Q;
        for (int nQ = 1; nQ <= Q; ++nQ) {
             for (int i=0; i"%d", &q.a[i]); 
            for (int i=1; i<=n; ++i) {
                p[i].c = 0.0;
                for (int j=0; jj) 
                    p[i].c += (ld)(q.a[j] - p[i].a[j]) * (q.a[j] - p[i].a[j]);
            }
            scanf("%d", &m);
            printf("the closest %d points are:\n", m);
            for (int i=1; i<=m; ++i, puts("")) {
                ld cur = 1e18; int id;
                for (int j=1; j<=n; ++j) {
                    if(chosen[j] == nQ) continue;
                    if(p[j].c < cur) cur = p[j].c, id = j;
                }
                chosen[id] = nQ;
                for (int j=0; j"%d ", p[id].a[j]);
            }
        }
    }
    
    return 0;
}

View Code

 

转载于:https://www.cnblogs.com/galaxies/p/bailian4091.html