c - 我已从 txt 文件读取数据并将其存储在结构体数组中，并希望按名称字段对数据进行排序

Question

此代码不会给出任何错误，但会显示旧的数组值而不按名称字段排序，它会读取将数据存储在结构体数组 Student 中的 txt 文件，这是结构体 person 的实例，然后使用代码对其进行排序并打印排序后的数组的结果。但它不起作用

#include < stdio.h > 
#include < string.h >

int main() {
    // read data from txt file and stores
    // in a struct array

    storeInarraySort();

}

int storeInarraySort() {

     // struct person with 4 fields
     struct person {
         char name[100];
         char address[100];
         char IDnumber[20];
         int age;
     };


     FILE * file = fopen("personout.txt", "r");

     // declares an struct array to store data
     struct person student[10];

     int k = 0;

     if (file != NULL)
     {
         char line[128]; /* or other suitable maximum line size */
         /* read a line */
         while (fgets(line, sizeof line, file) != NULL)
         {

             // stores values in struct array
             sscanf(line, " %99[^,], %99[^,], %19[^,], %d", student[k].name,
                 student[k].address, student[k].IDnumber, & student[k].age);
             k++;

         }
         printf("%d\n", k); // no of records in array

         fclose(file);


         // number of records k  r=k first for loop
         // inner for loop s=r+1
         //char temp;
         //struct person temp;

         for (int r = 0; r < k - 1; r++) {
             for (int s = r + 1; r < k; r++) {

                 if (strcmp(student[r].name, student[s].name) > 0) {

                     struct person temp = student[r];
                     //strcpy(temp,student[r]);
                     student[r] = student[s];
                     //strcpy(student[r],student[s]);
                     student[s] = temp;
                     //strcpy(student[s],temp);
                 }


             }


         }

         // prints struct array to check
         for (int t = 0; t < k; t++) {
             printf("%s\n %s\n %s\n %d\n ", student[t].name,
                 student[t].address, student[t].IDnumber, student[t].age);
         }

     }


}

Answer 1

使用选择排序进行排序。

void swap(int *xp, int *yp)  
{  
    int temp = *xp;  
    *xp = *yp;  
    *yp = temp;  
} 

void selectionSort(int arr[], int n)  
{  
    int i, j, min_idx;  

    // One by one move boundary of unsorted subarray  
    for (i = 0; i < n-1; i++)  
    {  
        // Find the minimum element in unsorted array  
        min_idx = i;  
        for (j = i+1; j < n; j++)  
        if (strcmp(arr[j].name , arr[min_idx].name) < 0)  
            min_idx = j;  

        // Swap the found minimum element with the first element  
        swap(&arr[min_idx], &arr[i]);  
    }  
}