HDU 1800 Flying to the Mars

字典树?!...不会用

排序+筛选A了, 开始没判断那一个人是否被筛掉, 也错了

真是太不小心了...hehe

 

2010-11-20 17:24:45    Accepted    1800    343MS    220K    1803 B    C    Y

 

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 3001

int elem[MAX];
char *hash;

/* 调整顶为top的m个元素的堆 */
void adjust_heap(int *elem, int top, int m)
{
    int i;
    int index; /* 保存当前小堆顶元素 */
    
    i = top * 2;
    index = elem[top-1];
    while (i <= m)
    {
        if (i < m && elem[i-1] < elem[i])
        {
            i++; /* 两个子元素之间的大小比较 */
        }
        if (index >= elem[i-1]) /* 堆已调整完闭 */
        {
            break;
        }
        
        elem[top-1] = elem[i-1]; /* 调整堆 */
        top = i; /* 修改堆指针 */
        
        i *= 2; /* 下一个循环条件 */
    }
    elem[top-1] = index;
} /* heap_sort(), adjust_heap(); */
/* 堆排序 */
void heap_sort(int *elem, int len)
{
    int i;
    int tmp;
    
    for (i = len / 2; i > 0; i--)
    {
        adjust_heap(elem, i, len);
    }
    
    for (i = len; i > 1; i--)
    {
        /* 每次都与堆顶元素交換 */
        tmp = elem[0];
        elem[0] = elem[i-1];
        elem[i-1] = tmp;
        
        adjust_heap(elem, 1, i - 1); /* 改变堆顶元素后要重新整理堆 */
    }
} /* heap_sort(), adjust_heap() */
/* 求取结果 */
void get_result(int *elem, int len)
{
    int i, j, k, cnt;
    
    if ((hash=(char *) calloc (MAX, sizeof(char))) == NULL) {
        printf("空间分配失败!\n");
        exit(-1);
    }
    memset(hash, '0', MAX);
    cnt = 0;
    for (i = 0; i < len; i++)
    {
        if ( hash[i] == '0' ) /* 此人还没有分组, 开始筛选 */
        {
            cnt++;
            k = elem[i];
            for (j = i; j < len; j++)
            {
                if (hash[j] == '0' && elem[j] > k) /* 一定要判断此人是否分组了 */
                {
                    k = elem[j];
                    hash[j] = '1';
                }
            }
        }
    }
    
    printf("%d\n", cnt);
    free( hash );
    hash = NULL;
}

int main()
{
    int i, N, num;
    
    while (scanf("%d", &N) == 1)
    {
        i = 0;
        while ( i < N )
        {
            scanf("%d", &elem[i++]);
        }
        
        heap_sort(elem, N);
        get_result(elem, N);
    }
    
    return 0;
}

 

 

 

 

/*
Input
Input file contains multiple test cases.
In a test case,the first line contains a single positive number N indicating
the number of soldiers.(0<=N<=3000)Next N lines :There is only one nonnegative
integer on each line , indicating the level number for each soldier.
( less than 30 digits);

 

Output
For each case, output the minimum number of broomsticks on a single line.

Sample Input
4
10 20 30 04
5

2 3 4 3 4
*/

2010-11-20 17:24:45    Accepted    1800    343MS    220K    1803 B    C    Y