Question

我一直在为这个编程任务工作，现在看起来像是永远，我还没有弄清楚我的错误。每次我编译程序然后输入一个文件我得到一个分段错误（核心转储）错误。我假设我的一个指针指向未分配的空间，但我不知道哪一个。有人能引导我朝着正确的方向前进吗？

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/time.h>
#define FALSE 0
#define TRUE !FALSE
int problem_size;

int Merge (long long int *numbers, int first, int last, int firstOne, int lastOne)
{
    long long int arrayOne[problem_size];
    long long int arrayTwo[problem_size];
    int x,y;

    for (x=0; x<last; x++)
        arrayOne[x] = numbers[x + first];

    for (y= last; y< lastOne; y++)
        arrayTwo[y - firstOne];

    int i = 0;
    int j = 0;
    int k = first;

    while ((i< last-first) && (j< lastOne - firstOne))
    {
        if (arrayOne[i] <= arrayTwo[j])
        {
            numbers[k] = arrayOne[i];
            i = i+1;
        }
        else
        {
            numbers[k] = arrayTwo[j];
            j = j+1;
        }
        k = k+1;
    }

    while (i < last-first)
    {
        numbers[k] = arrayOne[i];
        i = i+1;
        k = k+1;
    }

    while(j < lastOne - firstOne)
    {
        numbers[k] = arrayTwo[j];
        j = j + 1;
        k = k + 1;
    }
}

int MergeSort (long long int *numbers, int low, int high)
{
    if (high-low > 1)
    {
        int lowest = low;
        int highest = ((high-low)/2) + low;
        int lowestOne = highest;
        int highestOne = high;

        MergeSort(numbers, lowest, highest);
        MergeSort(numbers, lowestOne, highestOne);
        Merge(numbers, lowest, highest, lowestOne, highestOne);
    }
}

int unique3(long long int *numbers, int count, long long int *operations) {
    long long int basic_operations = 0;
    int i;

    MergeSort(numbers,0,count);

    for (i=0; i < count-2; i++)
        if(numbers[i] == numbers[i+1])
            return FALSE;
    *operations = basic_operations;
    return TRUE;
}


void read_array(char *file_name, long long int **return_numbers, int *return_size) {
    FILE *file; // file pointer used to read in file_name

    int count;
    int ii;
    long long int *numbers;

    file = fopen(file_name, "r"); // open the file for reading
    if (file == NULL) {
        // error openting the file, print error message
        perror(file_name);

        // set pointers to show failed state
        *return_numbers = NULL;
        *return_size = -1;
        return;
    }

    // read in the first line to determine how many numbers are in the list
    if (fscanf(file, "%d", &count) != 1) {
        // error openting the file, print error message
        perror("HERE");
        perror(file_name);

        fclose(file);

        // set pointers to show failed state
        *return_numbers = NULL;
        *return_size = -1;
        return;
    }

    // dynamically allocate an array to contain count number of long long ints
    numbers = (long long int *)malloc(sizeof(long long int)*count);

    // read in count numbers
    for(ii=0; ii < count; ii++) {
        // read in a number delimited by a comma
        if (fscanf(file, "%lld,", &(numbers[ii])) != 1) {
            // if char_count == -1, there was an error reading
            perror(file_name);

            free(numbers);
            fclose(file);

            // set pointers to show failed state
            *return_numbers = NULL;
            *return_size = -1;
            return;
        }
    }

    fclose(file);

    // set up pointer values
    *return_numbers = numbers;
    *return_size = count;
}

void timing(long long int *numbers, int count, int (*algorithm)(long long int *,
        int, long long int *), long long int *operations, int *unique,
        long long int *ms_time) {
    struct timeval start_tv;
    struct timeval end_tv;

    gettimeofday(&start_tv, NULL);
    *unique = algorithm(numbers, count, operations);
    gettimeofday(&end_tv, NULL);

    *ms_time = (end_tv.tv_sec - start_tv.tv_sec)*1000000L + (end_tv.tv_usec -
        start_tv.tv_usec);
}

int main(int argc, char *argv[]) {
    if(argc != 2) {
        printf("Invalid Number of Arguments\n");
        printf("Usage:\n");
        printf("%s <file_name>\n", argv[0]);
        printf("\tfile_name - name of the input file\n");
        printf("It is assumed that the first line of the input file contains\n");
        printf("the count of the numbers in the file. The second line is assume\n");
        printf("to be a comma separated list of integers.\n");
    }
    else {
        int count;
        long long int *numbers;
        long long int operations = 0;
        int is_unique;
        long long int ms_time;
        read_array(argv[1], &numbers, &count);

        if(count > 0){
            printf("Here");
            printf("%d ", count);
            timing(numbers, count, unique1, &operations, &is_unique, &ms_time);
            printf("(%d,%lld,%lld) ", is_unique, operations, ms_time);
        }
    }
    return 0;
}

Answer 1

您使用了数组大小problem_size，但从未定义过。由于你的数组是静态分配的，它也应该是一个编译时常量（例如#define，enum，literal（例如25），constexpr）

尝试：

#define problem_size 1024

我的程序段错误

1 个答案: