inputting strings into a multidimensional character array?

Question

While inputting the strings I am getting warnings like

error: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]'

In application

#include<stdio.h>
int main(void)
{
    char a[100][10];
    int s,i,k=0;
    scanf("%d",&s);
    for(i=0;i<s;i++)
    {
        scanf("%s",&a[i]);
    }
}

Answer 1

scanf("%s",&a[i]);
           ^ This will pass address of `a[i]` thus giving error.

As %s specifier expects a pointer to the first character in a character array. And using & with a[i] will evaluate char (*)[10].

Instead this should be done -

scanf("%9s", a[i]);

Answer 2

Yes because there is an difference between array and pointer to an array. You may use char *a[100]; as a pointer to array of 100 elements and use malloc/calloc every time to allocate space dynamically. The program would look like:

#include<stdio.h> 
#include<stdlib.h>         
int main(void)
{
    char *a[100];
    int s,i,k=0;
    scanf("%d",&s);
    for(i=0;i<s;i++)
    {
        a[i] = (char *) malloc (sizeof(char)*10);
        scanf("%s",a[i]);
        printf("%s",a[i]);
    }
}       

Answer 3

code: scanf("%s",&a[i]);

&a[i] point char **, because a is 2D char array.

code instead : scanf("%s",a[i]); will get right result