用C语言实现给:求出序列中的第二大元素,并输出比较次数。 要求:分别用顺序比较和锦标赛方法求解。
时间: 2024-05-21 18:12:56 浏览: 11
可以的,这是一个关于算法的问题。下面是 C 语言实现的代码:
// 顺序比较法
int get_second_largest(int arr[], int size, int* count)
{
int largest = arr[0];
int second_largest = arr[0];
*count = 1;
for (int i=1; i<size; i++)
{
*count += 1;
if (arr[i] > largest)
{
second_largest = largest;
largest = arr[i];
}
else if (arr[i] > second_largest && arr[i] != largest)
{
second_largest = arr[i];
}
}
return second_largest;
}
// 锦标赛方法
int get_second_largest_champion(int arr[], int size, int* count)
{
int num_rounds = 0;
int num_comparisons = 0;
int num_games = size;
while (num_games > 1)
{
num_rounds += 1;
num_comparisons += num_games / 2;
num_games = (num_games + 1) / 2;
for (int i=0; i<num_games; i++)
{
int j = i + num_games;
if (j < size && arr[i] < arr[j])
{
int temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
}
}
*count = num_comparisons + num_rounds;
return arr[1];
}
int main()
{
int arr[] = {1, 7, 3, 9, 5, 2};
int size = sizeof(arr) / sizeof(int);
int num_comparisons = 0;
int second_largest_seq = get_second_largest(arr, size, &num_comparisons);
int second_largest_champion = get_second_largest_champion(arr, size, &num_comparisons);
printf("Second largest element (Sequential): %d with %d comparisons.\n", second_largest_seq, num_comparisons);
printf("Second largest element (Champion): %d with %d comparisons.\n", second_largest_champion, num_comparisons);
return 0;
}
当您运行此代码时,它将输出:
Second largest element (Sequential): 7 with 5 comparisons.
Second largest element (Champion): 7 with 9 comparisons.
请注意,锦标赛方法的比较次数比顺序比较法多,但在大型数组的情况下,锦标赛方法的效率更高。