Programming algorithm-numeric code with more than half occurrences in an array (C)

numeric code with more than half occurrences in the array (C)

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Title: There is a number in the array that appears more than half the length of the array, please find this number.

1. Use the high-speed sequencing (QuickSort) method to match the median (middle) with the index , output the median value, and check whether it meets the requirements.

2. Use the counting method in turn.

Code:

Method 1:

/* * main.cpp * * Created on:2014.6.12 * author:spike *//*eclipse CDT, gcc 4.8.1*/#include <stdio.h> #include    <stdlib.h>int randominrange (int min, int max) {int random = rand ()% (Max-min + 1) + min; return random;}    void Swap (int* num1, int* num2) {int temp = *NUM1;    *NUM1 = *num2; *num2 = temp;} int Partition (int data[], int length, int start, int end) {if (data = = NULL | | length <= 0 | | Start < 0 | | end    ; = length) {return-1;    } int index = Randominrange (start, end);    Swap (&data[index], &data[end]);    int small = start-1;            for (index = start; index < end; + + index) {if (Data[index] < Data[end]) {+ + small;        if (small! = index) Swap (&data[index], &data[small]);    }} + small;    Swap (&data[small], &data[end]); return small;} BOOL Checkmorethanhalf (int* numbers, int length, int number) {int times = 0;for (int i=0; i<length; ++i) {if (numbers[i] = = number) ++times;} if (times*2 <= length) {return false;} return true;}  int Morethanhalfnum (int* numbers, int length) {if (numbers = = NULL | | length <= 0) return 0;int middle = length >> 1;int start = 0;int End = Length-1;int index = Partition (numbers, length, start, end), while (Index! = middle) {if (index > middle) {//Front part of number multiple end = Index-1;index = Partition (numbers, length, start, end);} else {start = Index+1;index = part Ition (numbers, length, index+1, start);}} int result = NUMBERS[MIDDLE];IF (! Checkmorethanhalf (numbers, length, result)) return 0;return result;}    int main (void) {int str[] = {1, 2, 3, 4, 4, 4, 5, 4, 4};    int result = Morethanhalfnum (str, 9);    printf ("reuslt =%d\n", result); return 0;}

Method 2:

/* * main.cpp * *  Created on:2014.6.12 *      author:spike *//*eclipse CDT, gcc 4.8.1*/#include <stdio.h> #inclu  De <stdlib.h>bool checkmorethanhalf (int* numbers, int length, int number) {int times = 0;for (int i=0; i<length; ++i) {if (numbers[i] = = number) times++;} if (times*2 < length) return False;return true;}  int Morethanhalfnum (int* numbers, int length) {if (numbers = = NULL | | length <= 0) return 0;int result = Numbers[0];int Times = 1;for (int i=0; i<length; ++i) {if (times = = 0) {result = Numbers[i];times = 1;} if (numbers[i] = = result) Times++;else times--;} if (! Checkmorethanhalf (numbers, length, result)) return 0;return result;} int main (void) {    int str[] =  {1, 2, 3, 2, 2, 2, 5, 2, 4};    int result = Morethanhalfnum (str, 9);    printf ("reuslt =%d\n", result);    return 0;}

Output:

REUSLT = 4

Programming algorithm-numeric code with more than half occurrences in an array (C)