查找数组中的第二大数

1 /**********************************************************

2 *DESCRIPTION *

3 * Find the second big number from an array. *

4 *PARAMETERS *

5 * array is the array you want to look up; size is t-*

6 * he array's length; psec is used to store the seco-*

7 * nd big number. *

8 *RETURN VALUE *

9 * Parameters invalid, -1 is returned; Not find the *

10 * second big number, -2 is returned; Success, 0 is *

11 * returned. *

12 **********************************************************/

13 int find_second_big_number(const int array[], int size, int *psec)

14 {

15 int max;

16 int second;

17 int i = 0;

18

19 if (NULL == array || NULL == psec || size < 2)

20 {

21 return -1;

22 }

23

24 /* Initialize max and second */

25 for (i = 1; i < size; i++)

26 {

27 if (array[0] != array[i])

28 {

29 if (array[0] > array[i])

30 {

31 max = array[0];

32 second = array[i];

33 }

34 else

35 {

36 max = array[i];

37 second = array[0];

38 }

39 break;

40 }

41 }

42

43 if (i == size)

44 {

45 return -2;

46 }

47

48 /* Find the second big number */

49 for (; i < size; i++)

50 {

51 if (max < array[i])

52 {

53 second = max;

54 max = array[i];

55 }

56 else if(max > array[i] && second < array[i])

57 {

58 second = array[i];

59 }

60 }

61

62 *psec = second;

63

64 return 0;

65 }