Adding strings to 2D array in C - c

Question

I'm trying to write a program that looks for the first empty space in a 2D array and adds a custom string to that space. I have tried some things that i found on the internet but none seem to work or match my specific scenario. This is it:
#include <stdio.h>
#include <string.h>
int tags[10] = {1,2,3,4,5};
char owners[10][10] = {"per1", "per2", "per3", "per4", "per5"};
int tagAdd;
char ownerAdd;
int i;
int addBool;
int j;
int len;
int main()
{
printf("Enter the tag ID you want to add: ");
scanf("%d", &tagAdd);
printf("Enter the tag owners name: ");
scanf("%d", &ownerAdd);
len = strlen(ownerAdd);
while (i<10)
{
if (tags[i] == 0)
{
tags[i] = tagAdd;
owners[i][len] = ownerAdd; //This is the part I can't figure out
addBool = 1;
}
if (addBool == 1)
{
break;
}
i++;
}
i = 0;
addBool = 0;
len = 0;
while (i<10)
{
printf("tag[%d]", tags[i]);
len = strlen(owners[i]);
printf(" is owned by ");
while (j < len)
{
printf("%c", owners[i][j]);
j++;
}
printf("\n\r");
i++;
j = 0;
}
}

Answer 1

You cannot do this:
char ownerAdd;
scanf("%d", &ownerAdd);
len = strlen(ownerAdd);
You are passing the incorrect types. ownerAdd is a single char, scanf
expects with %d a pointer to int, you are passing a pointer to char and if
scanf converts the value, it will overflow. And strlen expects a char*
which points to a valid string (0-terminated). You are doing all this wrong.
This would be correct:
char ownerAdd[100];
scanf("%99s", ownerAdd);
len = strlen(ownerAdd);
And for replacing a value:
owners[i][len] = ownerAdd; //This is the part I can't figure out
is also wrong, because owners[i] is a char[10], you have to do:
strncpy(owners[i], ownerAdd, sizeof owners[i]);
owners[i][sizeof(owners[i]) - 1] = 0;
to copy the string.
The next error is that you don't initialize i and do (the first loop)
while (i<10)
{
...
}
this is going to fail. Same thing with j, it is uninitialized.