Problem Description
There is an analog clock with two hands: an hour hand and a minute hand. The two hands form an angle. The angle is measured as the smallest angle between the two hands. The angle between the two hands has a measure that is greater than or equal to 0 and less than or equal to 180 degrees.
Given a sequence of five distinct times written in the format hh : mm , where hh are two digits representing full hours (00 <= hh <= 23) and mm are two digits representing minutes (00 <= mm <= 59) , you are to write a program that finds the median, that is, the third element of the sorted sequence of times in a nondecreasing order of their associated angles. Ties are broken in such a way that an earlier time precedes a later time.
For example, suppose you are given a sequence (06:05, 07:10, 03:00, 21:00, 12:55) of times. Because the sorted sequence is (12:55, 03:00, 21:00, 06:05, 07:10), you are to report 21:00.
Given a sequence of five distinct times written in the format hh : mm , where hh are two digits representing full hours (00 <= hh <= 23) and mm are two digits representing minutes (00 <= mm <= 59) , you are to write a program that finds the median, that is, the third element of the sorted sequence of times in a nondecreasing order of their associated angles. Ties are broken in such a way that an earlier time precedes a later time.
For example, suppose you are given a sequence (06:05, 07:10, 03:00, 21:00, 12:55) of times. Because the sorted sequence is (12:55, 03:00, 21:00, 06:05, 07:10), you are to report 21:00.
Input
The input consists of T test cases. The number of test cases (T) is given on the first line of the input file. Each test case is given on a single line, which contains a sequence of five distinct times, where times are given in the format hh : mm and are separated by a single space.
Output
Print exactly one line for each test case. The line is to contain the median in the format hh : mm of the times given. The following shows sample input and output for three test cases.
Sample Input
3
00:00 01:00 02:00 03:00 04:00
06:05 07:10 03:00 21:00 12:55
11:05 12:05 13:05 14:05 15:05
Sample Output
02:00
21:00
14:05
注意这题的排序是按照时针与分针的夹角大小来排序的
#include <stdio.h> #include <algorithm> #include <math.h> using namespace std; struct Node { int h,m; double r; }clock[10000]; int cmp(Node x,Node y) { if(x.r!=y.r) return x.r<y.r; return x.h<y.h; } int main() { int t; scanf("%d",&t); while(t--) { int i; for(i = 0;i<5;i++) { scanf("%d:%d",&clock[i].h,&clock[i].m); if(clock[i].h>12) clock[i].r = fabs(30.0*(clock[i].h-12)+clock[i].m/2.0-6.0*clock[i].m); else clock[i].r = fabs(30.0*clock[i].h+clock[i].m/2.0-6.0*clock[i].m); if(clock[i].r>180) clock[i].r = 360-clock[i].r; } sort(clock,clock+5,cmp); printf("%02d:%02d\n",clock[2].h,clock[2].m); } return 0; }