Thread: Help with adjacency matrix and scanf

Originally Posted by hollywoodcole

so I'm trying to figure how do I wirte my code accept this from standard in.
This is what I have so far: *note*this is not the whole program

Code:

scanf("%d", &nn);
	for (i = 0; i < nn; i++)
		for (j = 0; j < i; j++)
			cc =getchar()

This is some code I found that inputs random 1's and 0's into a matix

Code:

void complete_graph(int nv)
{
   int **mat;
   int i, j;

   mat = initialize_mat();

   for (i = 0; i < nv; i++) {
      for (j = 0; j < nv; j++)
         mat[i][j] = 1;
   }
   for (i = 0; i < nv; i++)
      mat[i][i] = 0; 
   print_mat(mat);
}

Sorry I wrote so much hope I got my point across
Thx in advance

Since you've posted some code and claim that you're trying yourself I'll give you some code for entering values from standard input and store in matrix.

Code:

#include <stdio.h>
#include <stdlib.h>
int main()
{   
    int nn;
    int** mat;
    int i, j;
    
    printf("Enter dimension of SQUARED matrix: ");
    fflush (stdout);
    scanf("%d", &nn);
    /* first goes allocation code for the matix*/
    mat = malloc(nn*sizeof(int*));/*allocate memory for pointers*/
    /*every pointer will point to each row*/
    for (i = 0; i < nn; ++i)
        mat[i] = malloc(nn*sizeof(int));/*allocate memory for numbers in each row*/
    printf("Enter elements row by row.\n");
    for (i = 0; i < nn; ++i)
        for(j = 0; j < nn; ++j)
              scanf("%d", &mat[i][j]);
    printf("You entered following matrix\n");
          
      for (i = 0; i < nn; ++i, printf("\n"))
        for(j = 0; j < nn; ++j)
              printf("%d ", mat[i][j]);

/*proper deallocation with free() is assumed*/ 
  
}

Do you really think your second code will produce matrix with random 1 and 0, I don't think so.
And that part mat = initialize_mat() is more than suspicios to me, initialize_mat has no arguements, why nv is not passed? How many elements can be stored in mat after calling initialize_mat?

Think about it!!!

Originally Posted by hollywoodcole

well could you just ignore the second part and explain to me the best way to use scanf to get the input?

In that case I suggest you to find a good tutorial on basics C.

Choose: here

>>best way to use scanf to get the input?
I wouldn't use scanf(). Try these for size:
http://faq.cprogramming.com/cgi-bin/...&id=1043284385
http://faq.cprogramming.com/cgi-bin/...&id=1043284385