hdu 5112 (2014北京现场赛 A题)

给出某个时刻对应的速度 求出相邻时刻的平均速度 输出最大值

Sample Input
2
3 // n
2 2 //t v
1 1
3 4
3
0 3
1 5
2 0

Sample Output
Case #1: 2.00
Case #2: 5.00

# include <iostream>
# include <cstdio>
# include <cstring>
# include <algorithm>
# include <string>
# include <cmath>
# include <queue>
# include <list>
# define LL long long
using namespace std ;

struct point
{
    int t ;
    int v ;
}a[10010];

bool cmp(point x , point y)
{
    return x.t < y.t ;
}

int main()
{
    //freopen("in.txt","r",stdin) ;
    int T ;
    scanf("%d" , &T) ;
    int Case = 0 ;
    while(T--)
    {
        int n , i ;
        Case++ ;
        double MAX = 0 ;
        scanf("%d" , &n) ;
        for (i = 0 ; i < n ; i++)
           scanf("%d %d" , &a[i].t , &a[i].v) ;
        sort(a , a+n , cmp) ;
        for (i = 0 ; i < n-1 ; i++)
        {
            double ans = fabs((a[i+1].v - a[i].v)*1.0/(a[i+1].t - a[i].t)*1.0) ;
            if (ans > MAX)
                MAX = ans ;
        }
        printf("Case #%d: %.2lf
" , Case , MAX) ;

    }

    return 0 ;
}