HDU - 5078 水题

题意：最大困难=距离 / 相邻时间

#include<cstring>
#include<cstdio>
#include<cmath>
#define ll double
ll num[][];
#define max(a, b)  (a)>(b)?(a):(b)

int main()
{
    int t;
    scanf("%d", &t);
    while (t--)
    {
        int n;
        scanf("%d", &n);
        for (int i = ; i < n; ++i)
            scanf("%lf%lf%lf", &num[][i], &num[][i], &num[][i]);
        double ans = ;
        for (int i = ; i < n; ++i)
        {
            double kk= sqrt((num[][i] - num[][i - ])*(num[][i] - num[][i - ]) + (num[][i] - num[][i - ])*(num[][i] - num[][i - ]))/(num[][i]-num[][i-]*1.0);
            ans = max(ans, kk);
        }
        printf("%.10lf\n", ans);
    }
}