问题描述
这是用于功课的,问题是要编写一个类似于学生数据库的程序,我可以在其中使用指针功能从结构s输入,打印和删除学生。但是,由于发生奇怪的事情,我无法删除学生记录。目标学生被删除,但其余学生记录(仅名称)被移动,只有第一个字符正确。请帮忙!
#include <stdio.h>
#include <string.h>
#define SIZE 50
typedef struct {
int id;
char name[50];
} Student;
void inputStud(Student *s,int size);
void printStud(Student *s,int size);
int removeStud(Student *s,int *size,char *target);
int main()
{
Student s[SIZE];
int size=0,choice;
char target[80],*p;
int result;
printf("Select one of the following options: \n");
printf("1: inputStud()\n");
printf("2: removeStud()\n");
printf("3: printStud()\n");
printf("4: exit()\n");
do {
printf("Enter your choice: \n");
scanf("%d",&choice);
switch (choice) {
case 1:
printf("Enter size: \n");
scanf("%d",&size);
printf("Enter %d students: \n",size);
inputStud(s,size);
break;
case 2:
printf("Enter name to be removed: \n");
scanf("\n");
fgets(target,80,stdin);
if (p=strchr(target,'\n')) *p = '\0';
printf("removeStud(): ");
result = removeStud(s,&size,target);
if (result == 0)
printf("Successfully removed\n");
else if (result == 1)
printf("Array is empty\n");
else if (result == 2)
printf("The target does not exist\n");
else
printf("An error has occurred\n");
break;
case 3:
printStud(s,size);
break;
}
} while (choice < 4);
return 0;
}
void inputStud(Student *s,int size)
{
int i=0;
char *p,dummy[50];
while (i<size) {
printf("Student ID: \n");
scanf("%d",&((s+i)->id));
printf("Student Name: \n");
scanf("\n");
fgets((s+i)->name,50,stdin);
if (p=strchr((s+i)->name,'\n')) *p = '\0';
i++;
}
}
void printStud(Student *s,int size)
{
int i;
printf("The current student list: \n");
if (size==0) printf("Empty array\n");
else {
for (i=0; i<size; i++) {
printf("Student ID: %d ",(s+i)->id);
printf("Student Name: %s\n",(s+i)->name);
}
}
}
int removeStud(Student *s,char *target)
{
int i,j,k;
if (*size==0) return 1;
for (i=0;i<*size;i++) {
if (strcmp(((s+i)->name),target)==0) {
--*size;
for (j=i; j<=*size; j++) {
k = j + 1;
*((s+j)->name) = *((s+k)->name);
(s+j)->id = (s+j+1)->id;
if ((s+j+1)->id=='\0') (s+j)->id = '\0';
}
return 0;
}
}
return 2;
}
解决方法
你快到了。
问题出在第97行:*((s + j)-> name)= *((s + k)-> name);
要使其生效,该指令应替换为:
strcpy((s + j)-> name,(s + k)-> name);
为什么:
您正在处理char数组,因此执行*((s + j)-> name)= *((s + k)-> name)的意思是:“输入s + k-的第一个char的值> name变成s + j-> name first char”。 相反,您要将s + k的全名复制到s + j的名称中。
关于如何使用strcpy,您可以看一下here