# producing a matrix of 1's and 0's

This is a discussion on producing a matrix of 1's and 0's within the C Programming forums, part of the General Programming Boards category; I am trying to produce a random matrix filled only with 1's and 0's but am struggling. I woudl appreciate ...

1. ## producing a matrix of 1's and 0's

I am trying to produce a random matrix filled only with 1's and 0's but am struggling. I woudl appreciate anyones advice!

This is my code so far:
insert
Code:
```#include <stdio.h>
#include <stdlib.h>
main(){
int a[10][10]={0};
int n,p, noofelements, randomno, rowpos, colpos;
int i,j,k;
srand(k);

printf("Enter the seed: ");
scanf("%d", &k);
printf("Enter the number of rows: ");
scanf("%d", &p);
printf("Enter the number columns: ");
scanf("%d", &n);
noofelements=n*p;
for (i=1; i<=noofelements; i++)
{
rowpos=rand()%n;
colpos=rand()%p;
a[rowpos][colpos]=i;
}
for (i=0; i<p; i++)
{
for (j=0; j<n; j++)
printf("%d\t", a[i][j]);
printf("\n");
}
}```
Emma

2. if you want only zeroes and 1 why do you insert something else?

a[rowpos][colpos]=i;

3. You also need to read in a value for k before doing
srand(k);

4. I am new to C programming and am finding it very difficult! I realise where I have gone wrong above, but still can't get a matrix with 0's and 1's in. now it just has weird numbers in. can anyone give me a hint?

Thanks Emma

insert
Code:
```#include <stdio.h>
#include <stdlib.h>
main(){
int n,p, rowpos, colpos;
int i,j;
int board[p][n];

printf("Enter the dimensions of the board , separate them with a comma:\n");
scanf("%d,%d", &p,&n);

for (i=0; i<p; i++)
{
for (j=0; j<n; j++)
printf("%d\t", board[i][j]);
printf("\n");
}
}```

5. You are not setting the board[i][j] to anything, are you?

--
Mats