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NEStenerus nester
Asked:2020-11-18 03:15:45 +0800 CST2020-11-18 03:15:45 +0800 CST

对大量数据进行排序c ++

  • 772

所以，我需要对csv文件进行排序，它有114318条记录，我需要使用快速排序，我写了一个程序，但是这里有问题，当排序超过2000条记录时，会出现错误

Необработанное исключение по адресу 0x00D21F49 в proj.exe: 0xC00000FD: Stack 
overflow (параметры: 0x00000001, 0x004A2FF8).

互联网说问题是堆栈溢出正在发生，我将所有数组移动到全局区域，但它没有帮助，告诉我，我怎样才能对整个文件进行快速排序？这是代码：

int temperature(const Star* x)
{
    int psefdo_temperature= 0;
    if (x->spectral_type[0] == 'O')
        psefdo_temperature = 70;
    if (x->spectral_type[0] == 'B')
        psefdo_temperature = 60;
    if (x->spectral_type[0] == 'A')
        psefdo_temperature = 50;
    if (x->spectral_type[0] == 'F')
        psefdo_temperature = 40;
    if (x->spectral_type[0] == 'G')
        psefdo_temperature = 30;
    if (x->spectral_type[0] == 'K')
        psefdo_temperature = 20;
    if (x->spectral_type[0] == 'M')
        psefdo_temperature = 10;
    psefdo_temperature += -1 * (x->spectral_type[1] - '0');
    return psefdo_temperature;
}

void quicksort_temperature(Star array[], int lo, int hi)
{
    if (hi - lo > 1)
    {
        Star pivot = array[lo];
        int j = lo + 1;
        for (int i = lo + 1; i < hi; i++)
            if (temperature(&array[i]) <= temperature(&pivot))
            {
                Star temp = array[i];
                array[i] = array[j];
            array[j] = temp;
            j++;
        }
        quicksort_temperature(array, lo, j - 1);
        quicksort_temperature(array, j, hi);
    }
}


int main()
{
    Star* p = (Star*)malloc(120000 * sizeof(Star));
    int number_of_stars = 114318;
    FILE* f = fopen("1.csv", "r");
    char header[200];
    fscanf(f, "%s\n", header);
    for (int i = 1; i < number_of_stars; i++)
    {
        fscanf(f, "%ld,%s,%lf,%lf,%lf,%lf,%s,%lf,%lf,%lf,%[^\n]\n",
        &p[i].hip, p[i].proper_name, &p[i].right_ascension, &p[i].declination,
        &p[i].magnitude, &p[i].absolute_magnitude, p[i].spectral_type, &p[i].x,
        &p[i].y, &p[i].z, p[i].constellation);
    }
    fclose(f);

    printf("sorting start");

    quicksort_temperature(p, 0, number_of_stars);

    char s[] = "sorted_by_temperature.txt";
    save_stars(s, p, number_of_stars);
    free(p);
    return 0;
}

这是进行排序的代码部分，文件中有几个字段，我按字段排序，spectral_type格式中有数据латинская заглавная буква, цифра，示例：G1 B0 A3如何使程序工作number_of_stars >2000？

PS只有在不比给定算法慢的情况下才能更改排序算法

PPS之星公告：

struct star
{
    long int hip;
    char proper_name[20];
    double right_ascension;
    double declination;
    double magnitude;
    double absolute_magnitude;
    char spectral_type[15];
    double x, y, z;
    char constellation[5];
};
typedef struct star Star;`
c++

1 个回答

  1. Best Answer

    如果您在标签中指定了 C++，则如下所示：

    bool lessClass(const Star& a, const Star& b)
{
    const char * cls = "OBAFGKM";

    const char * ast = strchr(cls,a.spectral_type[0]);
    if (ast == 0) ast = cls + 7;

    const char * bst = strchr(cls,b.spectral_type[0]);
    if (bst == 0) bst = cls + 7;

    if (ast < bst) return true;
    if (ast > bst) return false;
    return a.spectral_type[1] < b.spectral_type[1];
}

int main(int argc, const char * argv[])
{
    Star* p = (Star*)malloc(120000 * sizeof(Star));
    int number_of_stars = 114318;

    ...

    sort(p,p+number_of_stars,lessClass);
}

    如果是 C，那么是这样的：

    int compClass(const void * astar, const void * bstar)
{
    const char * cls = "OBAFGKM";

    const Star * a = (const Star *)astar;
    const Star * b = (const Star *)bstar;

    const char * ast = strchr(cls,a->spectral_type[0]);
    if (ast == 0) ast = cls + 7;

    const char * bst = strchr(cls,b->spectral_type[0]);
    if (bst == 0) bst = cls + 7;

    if (ast < bst) return -1;
    if (ast > bst) return 1;
    return a->spectral_type[1] - b->spectral_type[1];
}

int main(int argc, const char * argv[])
{
    Star* p = (Star*)malloc(120000 * sizeof(Star));
    int number_of_stars = 114318;

    //...

    qsort(p,number_of_stars,sizeof(Star),compClass);
}
    • 3

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