CSP-202009-1-称检测点查询

解题思路

• 本题的时间复杂度貌似没有限制，直接暴力枚举就能
• 知识盲点：sort()函数-升序排序
  • #include <algorithm>
  • 给名为dis，长度为n的数组排序sort(new_dis, new_dis + n);

#include <iostream>
#include <algorithm>
using namespace std;
int main() {
    int n, x, y, flag = 0, dis[205] = {}, new_dis[205] = {};
    cin >> n >> x >> y;
    for (int i = 0; i < n; i++)
    {
        int xi, yi;
        cin >> xi >> yi;
        dis[i] = (x - xi) * (x - xi) + (y - yi) * (y - yi);
        new_dis[i] = dis[i];
    }
    // 升序排序
    sort(new_dis, new_dis + n);
    int min = new_dis[0];
    bool isChange = 1;
    for (int i = 0; i < n; i++)
    {
        if (new_dis[i] != min)
        {
            min = new_dis[i];
            isChange = 1;
        }
        // new_dis可能有重复值，不检查相同的值
        if (isChange)
        {
            for (int j = 0; j < n; j++)
            {
                if (dis[j] == min)
                {
                    cout << j + 1 << endl;
                    flag++;
                }
                if (flag == 3) break;
            }
            isChange = 0;
        }        
        if (flag == 3) break;
    }
    
    return 0;
}