c - 段错误和结构

Question

我希望该程序读取输入文件，然后将单个单词及其频率保存到结构中，然后将该结构的内容打印到输出文件中。我遇到段错误，但我不知道为什么。我也不确定我的程序是否正确编写。感谢您的帮助。

#include "stdio.h"
#include "stdlib.h"
#include "string.h"

struct string_count
{
char *str;
int *str_freq;
};

int main(int argc, char* argv[])
{
int i=0, j, temp;
char *str_temp, *temp2;
struct string_count *word ;
FILE *fp1, *fp2;

fp1 = fopen("input.txt", "r");
if( fp1 == NULL )
{
     printf("Input file can't be opened");
     exit(1);
}    
fp2 = fopen("output.txt", "w");
if (fp2 == NULL)
{ 
    printf("Error: Output file can't be created");
    exit (1);
}
fgets(str_temp, 50000000, fp1);
str_temp = (char*)malloc(5000000*sizeof(char));
fclose(fp1);
word->str = (char*)malloc(strlen(str_temp)*sizeof(char));
word->str_freq = (int*)malloc(strlen(str_temp)*sizeof(int));
word->str[0] = (char*)strtok(str_temp, " ,;(){}""'");
word->str_freq[0] = 0;
word->str_freq[0]++;
while(getc(fp2) != EOF)
{
    i++;
    word->str[i] = (char*)strtok(NULL, " ,;(){}""'");
    for (j=0, word->str[i]=0;j < i;j++)
    {
        if( word->str[i] = word->str[j]) word->str_freq[i]++;
    }
}
for (j = 1; j < i; j++)
{
    if (word->str_freq[j] > word->str_freq[j - 1])
    {
          temp = word->str_freq[j];
          word->str_freq[j] = word->str_freq[j - 1];
          word->str_freq[j - 1] = temp;
          str_temp = word->str[j];
          word->str[j] = word->str[j - 1];
          word->str[j - 1] = str_temp;
    }   
}
for (j = 0; j < i; j++)
{
    fprintf(fp2, "%s    %d\n", word->str[j], word->str_freq[j]);             
}
fclose(fp2);
system("PAUSE");
}

Answer 1

你首先在这里犯了很多错误

str_temp = (char*)malloc(5000000*sizeof(char));

在 fgets 行之前和这里也使用它

word->str = (char*)malloc(strlen(str_temp)*sizeof(char));

这里您还没有为字结构指针分配内存并进一步将内存分配给其其他成员。纠正这些