压缩数据

左手的ㄟ右手 2022-06-16 03:40 155阅读 0赞

给定一串数据，按照规律进行压缩，比如：  
压缩前：1,1,1,1,2,2,2,3,8,3,1,1,2,7  
压缩后：4,1,3,2,-3,3,8,3,2,1,-2,2,7

参考代码1：

#include <stdio.h>
    #include <malloc.h>
    #include <math.h>
    
    enum EmState
    {
        emInit    = 0,
        emSame    = 1,
        emDif     = 2,
    };
    
    int main()
    {
        int arr[] = { 1, 1, 1, 1, 2, 2, 2, 3, 8, 3, 1, 1, 2, 7};
        //int arr[] = {1,2,2,3,4,8,9,9,10,10,10,9,10,11,12,13,13,14,14,15};
        int nSize = sizeof(arr) / sizeof(arr[0]);
        int *pCnt = (int*)malloc((nSize + 1) * sizeof(int));
        int i, j, nLen = 0, nTemp = arr[0];
        enum EmState lastState = emInit;
        pCnt[nLen++] = 0;
        for (i = 1; i < nSize; i++)
        {
            if (arr[i] == nTemp)
            {
                if (lastState == emDif)
                    pCnt[nLen++] = -(i - 1);//不想另外用标记，所以如果是不同的直接标记为负数
                lastState = emSame;
            }
            else
            {
                if (lastState == emSame)
                {
                    if (i - arr[nLen] > 1)
                    {
                        pCnt[nLen++] = i;
                        lastState = emInit;
                    }
                }
                else
                    lastState = emDif;
            }
            nTemp = arr[i];
        }
        pCnt[nLen++] = lastState == emSame ? i : -i;
    
        for (i = 1; i < nLen; i++)
        {
            if (i > 1) printf(",");
            if (pCnt[i] > 0)
            {
                printf("%d,%d", abs(pCnt[i]) - abs(pCnt[i - 1]), arr[abs(pCnt[i - 1])]);
            }
            else
            {
                printf("%d", abs(pCnt[i - 1]) - abs(pCnt[i]));
                for (j = abs(pCnt[i - 1]); j < abs(pCnt[i]); j++)
                    printf(",%d", arr[j]);
            }
        }
        printf("\n");
        free(pCnt);
        return 0;
    }

参考代码2：

#include <stdio.h>
    
    enum EmState
    {
        emInit    = 0,
        emSame    = 1,
        emDif     = 2,
    };
    
    int main()
    {
        int arr[] = { 1, 1, 1, 1, 2, 2, 2, 3, 8, 3, 1, 1, 2, 7};
        //int arr[] = {
       1,2,2,3,4,8,9,9,10,10,10,9,10,11,12,13,13,14,14,15};
        int nSize = sizeof(arr) / sizeof(arr[0]);
        int i, j, nStartPos = 0, nTemp = arr[0];
        enum EmState lastState = emInit;
        for (i = 1; i < nSize; i++)
        {
            if (arr[i] == nTemp)
            {
                if (lastState == emDif)
                {
                    i--;
                    if (i > nStartPos)
                    {
                        if (nStartPos > 0) printf(",");
                        printf("%d", nStartPos - i);
                        for (j = nStartPos; j < i; j++)
                            printf(",%d", arr[j]);
                    }
                    nStartPos = i;
                    lastState = emInit;
                }
                else
                    lastState = emSame;
            }
            else
            {
                if (lastState == emSame)
                {
                    if (i - nStartPos > 1)
                    {
                        if (nStartPos > 0) printf(",");
                        printf("%d,%d", i - nStartPos, arr[nStartPos]);
                        nStartPos = i;
                        lastState = emInit;
                    }
                }
                else
                    lastState = emDif;
            }
            nTemp = arr[i];
        }
        if (nStartPos > 0) printf(",");
        if (lastState == emSame)
            printf("%d,%d", i - nStartPos, arr[i - 1]);
        else
        {
            if (i > nStartPos)
            {
                printf("%d", nStartPos - i);
                for (j = nStartPos; j < i; j++)
                    printf(",%d", arr[j]);
            }
        }
        printf("\n");
        return 0;
    }

运行结果：  
![这里写图片描述][SouthEast]

[SouthEast]: /images/20220616/0c58c38ae11d44148fd137e76521c33b.png