I want to initialize a couple of arrays which are members of a struct which is passed to a function by reference. Appreciate any help.
typedef struct Snake_pos
{
char field[10][10];
int Y[10];
int X[10];
}snake_pos;
int main()
{
snake_pos pos1;
pos_init(&pos1);
return 0;
}
void pos_init(snake_pos *pos1)
{
pos1->X={};
pos1->Y={};
pos1->field={};
}
You can only use the syntax = {} when defining the variable. So to zero every member you can either define it as
snake_pos pos1 = { 0 };
Or if it is passed to a function, like this
void pos_init(snake_pos *pos1)
{
memset(pos1, 0, sizeof *pos1);
}
{} in a function which was passed a defined variable. I posted two solutions. In the first case snake_pos pos1 = { 0 }; is a definition which also initialises, and the data would be easy to change. In the second case the function would be passed a defined variable to initialise, but since he did not state what values to initialise I gave the trivial solution, which he was happy to accept. If you can post a better answer, please edit your earlier one and revive it instead of downvoting me.You can access any array element inside of an array through a structure pointer this way :
- for 1 D array :
structure_pointer->array_valiable[index1]- for 2 D array :
structure_pointer->array_valiable[index1][index2]
so now, you can initialize each member of arrays X , Y and field of structure snake_pos using scanf() this way :
#include <stdio.h>
typedef struct Snake_pos
{
char field[10][10];
int Y[10];
int X[10];
}snake_pos;
void pos_init(snake_pos *pos1)
{
int i,j;
//initializing each member
//of array X
for(i=0;i<10;i++)
scanf("%d",&pos1->X[i]);
//of array Y
for(i=0;i<10;i++)
scanf("%d",&pos1->Y[i]);
//of the two dimensional array field
for(i=0;i<10;i++)
for(j=0;j<10;j++)
scanf(" %c",&pos1->field[i][j]);
//notice the space before %c is to consume white spaces returning from before scanf's
}
int main()
{
snake_pos pos1;
pos_init(&pos1);
return 0;
}
Note : if you want to initialize all members to a single fixed value, then you can instead of using scanf() in for loop, assign the value this way :
for(i=0;i<10;i++) //initializes all members with a value of 0 pos1->X[i]=0;
If you want to initialize with zero's, Why not memset the structure ?
void pos_init(snake_pos *pos1)
{
memset(pos1, 0, sizeof(snake_pos));
}