(a)
#include<stdio.h>
#include<string.h>
int main()
{
char *str1 = "United";
char *str2 = "Front";
char *str3;
str3 = strcat(str1, str2);
printf("\n%s", str3);
return 0;
}Error: As the str3 is declared but not defined, so it is an only void pointer, so without allocating memory to it, we cannot store anything to it.
(b)
#include<stdio.h>
int main()
{
int arr[] = { 'A', 'B', 'C', 'D' };
int i;
for (i = 0; i <= 3; i++)
printf("\n%d", arr[i]);
return 0;
}Error: No error.
(c)
#include<stdio.h>
int main()
{
char arr[8] = "Rhombus";
int i;
for (i = 0; i <= 7; i++)
printf("\n%d", *arr);
arr++;
return 0;
}Error: In arr++ statement. As you can see that arr[8] is initialized at the time of declaration. So, in that case, we cannot assign anything to arr, and statement arr++ is execute as arr = arr + 1, which is illegal.
