OXPattern

10000的随机数组由ox组成，查找数组中oox...x(任意x)oox....x(任意x)o的个数

enum {
    DATA_SIZE = 10000,
};

enum enum_status {
    STATUS_FOUND = 0,
    STATUS_ERR,
    STATUS_NOT_FOUND, //ALL 'X'
};

enum_status findOOX(int data[DATA_SIZE], int start, int& index) {
    for(int i = start; i < DATA_SIZE - 2; i++)     {
        if(data[i] == 'O' && data[i + 1] == 'O' && data[i + 2] == 'X') {
            index = i;
            return STATUS_FOUND;
        }

        if(data[i] == 'O' && (data[i + 1] != 'O' || data[i + 2] != 'X'))         {
            index = i;
            return STATUS_ERR;
        }
    }
    return STATUS_NOT_FOUND;
}

bool findO(int data[DATA_SIZE], int start, int& index) {
    for(int i = start; i < DATA_SIZE; i++)     {
        if(data[i] == 'O')         {
            index = i;
            return true;
        }
    }
    return false;
}

int test_main(int data[DATA_SIZE]) {
    enum_status stat = STATUS_NOT_FOUND;
    int count = 0;
    int index = 0;

    for(int i = 0; i < DATA_SIZE; i++)     {
        stat = findOOX(data, i, index);
        if(stat == STATUS_NOT_FOUND)         {
            break;
        }

        if(stat == STATUS_ERR)         {
            i = index;  //TODO
            continue;
        }
        i = index + 3;

        stat = findOOX(data, i, index);
        if(stat == STATUS_NOT_FOUND)         {
            break;
        }

        if(stat == STATUS_ERR)         {
            i = index;  //TODO
            continue;
        }
        i = index + 3;

        if(findO(data, i, index))        {
            count++;
            i = index;
        }
        else         {
            break;
        }
        
    }

    return count;
}

 用于生成测试用例的demo：

#include <stdio.h>
#include <stdlib.h>

#define  SIZE 10000

int test_main(int data[SIZE]);

static int data[SIZE];

static void build_data(void)
{
    for (int a = 0; a < SIZE; a++)
    {
        data[a] = (rand() % 2) ? 'O' : 'X';
    }
}


void main(void)
{
    for (int l = 0; l < 10; l++)
    {
        build_data();

        printf("%d\n", test_main(data));
    }
    system("pause");
}