CODEWITHSUNDEEP
cstringmultidimensional-array
Pranav Sharma
Pranav Sharma

Reputation: 41

How to input a string in a 2d array in C?

If i want to take an input in a 2d array with each string in one row, and the next in the other(i.e. change the row on pressing enter). How can i do that in C. C doesnt seem to have convenient "String" Handling. I obviously mean doing so without the use of getchar().

Upvotes: 2

Views: 73219

Answers (4)

Ignatios Papathemistokleous
Ignatios Papathemistokleous

Reputation: 1

I prefer no to use scanf. Instead you can use fgets.

#include <stdio.h>
#include <string.h>

int main()
{
 char str[array_size][char_size] = {{0}};
 int i = 0;

  for(i=0;i<array_size;i++)
  {
    fgets(str[i], array_size, stdin);
    getchar(); // get char is used to clear the buffer and get rid of the new line fgets leaves behind
  }
  return 0;
}

Upvotes: 0

Brijesh Gajjar
Brijesh Gajjar

Reputation: 562

#include<stdio.h>

main()

{

char student_name[5][25];

    int i;

    for(i=0;i<5;i++)
    {
       printf("\nEnter a string %d: ",i+1);
       scanf(" %[^\n]",student_name[i]);
    }

}

u can read strings using 2d array without using getchar() by putting space in scanf(" %[^\n]") ; before %[^\n]!

Upvotes: 4

StoryTeller - Unslander Monica
StoryTeller - Unslander Monica

Reputation: 170044

An alternative to using malloc and filling up an array of pointers with buffers of a fixed size, would be to allocate a 2d array (in static storage or on the stack) and fill it up. KingsIndian modifed code example would than look like this:

#include <stdio.h>

int main()
{
 char str[2][256] = {{0}};
 int i = 0;

  for(i=0;i<2;i++)
  {
    scanf("%255s", &str[i][0]);
  }
  return 0;
}

If all strings you expect to get are no longer than some size, than this approach will spare you the need to deal with freeing the memory yourself. It is less flexible however, meaning that you can't fit the size of an individual buffer to the string it contains.

EDIT

Adding to the information in the comment, to read a string that is terminated only by a new-line, rather than by any whitespace:

scanf("%255[^\n]", str[i]);

Upvotes: 0

rashok
rashok

Reputation: 13414

3 ways are there which are mentioned below.

If you know the maximum number of strings and maximum number of chars, then you can use the below way to declare a 2D character array.

char strs[MAX_NO_OF_STRS][MAX_NO_CHARS] = {0};
for (i = 0; i < MAX_NO_OF_STRS; i++)
{
    scanf("%s", strs[i]);
}

If you know the maximum number of strings, and you dont want to waste the memory by allocating memory for MAX_NO_CHARS for all strings. then go for array of char pointers.

char temp[MAX_NO_CHARS] = {0};
char *strs[MAX_NO_OF_STRS] = NULL;
for (i = 0; i < MAX_NO_OF_STRS; i++)
{
    scanf("%s", temp);
    strs[i] = strdup(temp);
}

If you know the maximum number of strings during run time means, you can declare a double pointer of char. Get the number of strings n from user and then allocate memory dynamically.

char temp[MAX_NO_CHARS] = {0};
char **strs = NULL;
int n = 0;
scanf("%d", &n);
strs = malloc(sizeof(char*) * n);
for (i = 0; i < n; i++)
{
    scanf("%s", temp);
    strs[i] = strdup(temp);
}

Upvotes: 5

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