I am writing this code using dynamic memory allocation, for student records as indicated, this code suppose to be simple , I am obviously allocating elements in their correct places the right way, but when it comes to printing them, it gives me a "core dumped
" error ! what is wrong ?
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void main()
{
char **firstname;
char **lastname;
float *score;
int number_of_records,i,j,ctr=1,row=15,col=20;
/*ctr is to keep track of the student's number (makes it easier to
the user), it starts with (1)*/
firstname=malloc(row*sizeof(char*));
for(i=0;i<row;i++)
{
firstname[i]=malloc((col+1)*sizeof(char));
}
lastname=malloc(row*sizeof(char*));
for(i=0;i<row;i++)
{
lastname[i]=malloc((col+1)*sizeof(char));
}
printf("\nPlease indicate number of records you want to enter (min 2, max 15): ");
scanf("%d",&number_of_records);
score=malloc(row*sizeof(float));
printf("\nPlease input records of students\n(enter a new line after"
"each record), with following format:\nfirst name last name score ");
for (i=0;i<number_of_records;i++)
{
printf("\nEnter record for student %d : ",ctr);
scanf("%s %s %f",firstname[i],lastname[i],score[i]);
ctr++; /*ctr is to keep track of student number
(makes it easy to the user) */
}
for (i=0;i<number_of_records;i++)
{
printf("%s %s %f\n",firstname[i],lastname[i],score[i]);
}
}
Please change this:
for (i=0;i<number_of_records;i++)
{
printf("\nEnter record for student %d : ",ctr);
scanf("%s %s %f",&firstname[i],&lastname[i],&score[i]);
ctr++; /*ctr is to keep track of student number (makes it easy to the user) */
}
to this
for (i=0;i<number_of_records;i++)
{
printf("\nEnter record for student %d : ",ctr);
scanf("%s %s %f",firstname[i],lastname[i],&score[i]);
ctr++; /*ctr is to keep track of student number (makes it easy to the user) */
}
And it will work. The reason is that firstname[i]
and lastname[i]
are already pointers
; you do not need to use &
operator for them.
P.S. Also, since you are using C, do no cast the returning values from malloc
or realloc
. It will be done automatically.