#include <stdio.h>
#include <stdlib.h>

typedef struct Student Student;
    struct Student
    {
        int math_grade;
        int chinese_grade;
        int english_grade;
        char student_name[];
    };
    int main()
    {
        Student studentA;
        Student studentB;
        Student studentC;
        //引导输入第一个学生的数据。
        printf("请输入第一个学生的名字：");
        scanf("%s",studentA.student_name);
        printf("\n");
        printf("请输入%s的数学成绩:",studentA.student_name);
        scanf("%d",&studentA.math_grade);
        printf("\n");
        printf("请输入%s的语文成绩：",studentA.student_name);
        scanf("%d",&studentA.chinese_grade);
        printf("\n");
        printf("请输入%s的英语成绩：",studentA.student_name);
        scanf("%d",&studentA.english_grade);
        printf("%d %d %d",studentA.math_grade,studentA.chinese_grade,studentA.english_grade);
        printf("\n");
        //引导输入第二个学生的数据。
        printf("请输入第二个学生的名字：");
        scanf("%s",studentB.student_name);
        printf("\n");
        printf("请输入%s的数学成绩:",studentB.student_name);
        scanf("%d",&studentB.math_grade);
        printf("\n");
        printf("请输入%s的语文成绩：",studentB.student_name);
        scanf("%d",&studentB.chinese_grade);
        printf("\n");
        printf("请输入%s的英语成绩：",studentB.student_name);
        scanf("%d",&studentB.english_grade);
        printf("%d %d %d",studentB.math_grade,studentB.chinese_grade,studentB.english_grade);
        printf("\n");
        //引导输入第三个学生的数据。
        printf("\n");
        printf("请输入第三个学生的名字：");
        scanf("%s",studentC.student_name);
        printf("\n");
        printf("请输入%s的数学成绩:",studentC.student_name);
        scanf("%d",&studentC.math_grade);
        printf("\n");
        printf("请输入%s的语文成绩：",studentC.student_name);
        scanf("%d",&studentC.chinese_grade);
        printf("\n");
        printf("请输入%s的英语成绩：",studentC.student_name);
        scanf("%d",&studentC.english_grade);
        printf("%d %d %d",studentC.math_grade,studentC.chinese_grade,studentC.english_grade);
        printf("\n");
        printf("下面输出成绩单：\n");
        putchar(10);
        //输出成绩单。
        printf("姓名\t数学\t语文\t英语\t\n");
        printf("%s\t%d\t%d\t\n",studentA.student_name,studentA.math_grade,studentA.chinese_grade,studentA.english_grade);
        printf("%s\t%d\t%d\t\n",studentB.student_name,studentB.math_grade,studentB.chinese_grade,studentB.english_grade);
        printf("%s\t%d\t%d\t\n",studentC.student_name,studentC.math_grade,studentC.chinese_grade,studentC.english_grade);
        system("pause");
        return 0;
    }



        

下面是程序 运行截图，请问为什么会出现这种情况。。。


本人使用的编译器：visual studio 2010

#include <stdio.h>
#include <stdlib.h>


typedef struct Student
{
        int math_grade;
        int chinese_grade;
        int english_grade;
        char student_name[];
}score;


 int main()

 {
        score *studentA;
        score *studentB;
        score *studentC;

        studentA = (score *)malloc(sizeof(studentA));
        studentB = (score *)malloc(sizeof(studentB));
        studentC = (score *)malloc(sizeof(studentC));

        //引导输入第一个学生的数据。
        printf("请输入第一个学生的名字：");
        scanf("%s", studentA->student_name);
        printf("\n");

        printf("请输入%s的数学成绩:", studentA->student_name);
        scanf("%d",&studentA->math_grade);
        printf("\n");

        printf("请输入%s的语文成绩：",studentA->student_name);
        scanf("%d",&studentA->chinese_grade);
        printf("\n");

        printf("请输入%s的英语成绩：",studentA->student_name);
        scanf("%d",&studentA->english_grade);
        printf("%d %d %d",studentA->math_grade,studentA->chinese_grade,studentA->english_grade);
        printf("\n");

        
        //引导输入第二个学生的数据。
        printf("请输入第二个学生的名字：");
        scanf("%s",studentB->student_name);
        printf("\n");
        printf("请输入%s的数学成绩:",studentB->student_name);
        scanf("%d",&studentB->math_grade);
        printf("\n");
        printf("请输入%s的语文成绩：",studentB->student_name);
        scanf("%d",&studentB->chinese_grade);
        printf("\n");
        printf("请输入%s的英语成绩：",studentB->student_name);
        scanf("%d",&studentB->english_grade);
        printf("%d %d %d",studentB->math_grade,studentB->chinese_grade,studentB->english_grade);
        printf("\n");
        //引导输入第三个学生的数据。
        printf("\n");
        printf("请输入第三个学生的名字：");
        scanf("%s",studentC->student_name);
        printf("\n");
        printf("请输入%s的数学成绩:",studentC->student_name);
        scanf("%d",&studentC->math_grade);
        printf("\n");
        printf("请输入%s的语文成绩：",studentC->student_name);
        scanf("%d",&studentC->chinese_grade);
        printf("\n");
        printf("请输入%s的英语成绩：",studentC->student_name);
        scanf("%d",&studentC->english_grade);
        printf("%d %d %d",studentC->math_grade,studentC->chinese_grade,studentC->english_grade);
        printf("\n");
        printf("下面输出成绩单：\n");
        putchar(10);
        
    
        //输出成绩单。
        printf("姓名\t数学\t语文\t英语\t\n");
        printf("%s\t%d\t%d\t%d\n",studentA->student_name,studentA->math_grade,studentA->chinese_grade,studentA->english_grade);
        printf("%s\t%d\t%d\t%d\n",studentB->student_name,studentB->math_grade,studentB->chinese_grade,studentB->english_grade);
        printf("%s\t%d\t%d\t%d\n",studentC->student_name,studentC->math_grade,studentC->chinese_grade,studentC->english_grade);
  
        return 0;
    }

这个是可以的，至于你那个，好像是什么分配内存的问题，我也不太清楚，也是菜鸟一只，不好意思啊

楼上正解
printf("%s\t%d\t%d\t\n",studentA.student_name,studentA.math_grade,studentA.chinese_grade,studentA.english_grade);

只有两个整形说明符号，后面要输出三个~~