matrix challenge

Okay so Ive made a program that only asks a user for the # of columns of a matrix and then determines the rows of the matrix and displays it. The problem is if the user for example for a 2 by 2 matrix enters only 3 values then the program doesnt work. I want the program to show 2 rows for 3 values and then maybe put 0 as the fourth value. Please help

Code:

#include<stdio.h>
#include<stdlib.h>

int  main()
{
  int m,x, n, c = 0, d,k, matrix[10][10], transpose[10][10], product[10][10];

  printf("Enter the number of columns of matrix ");
  scanf("%d",&m);
  if(m<=0){
    printf("You entered a invalid value.");
    exit(0);
  }
  else{
    printf("Enter the elements of matrix \n");

    for( c = 0 ; c < 10 ; c++ )
      {
        for( d = 0 ; d < m ; d++ )
          {
            scanf("%d",&matrix[c][d]);
            if (matrix[c][d] == 99) // 'x' is character variable I declared to use as a break
           break;
            // c = c+1;

          }
        if (matrix[c][d] == 99)
          break;
      }
  }

  printf("\nHere is your matrix:\n");
  int i;

  for(i=0;i<c;i++)
    {
      for(d=0;d<m;d++)
        {
          /* if( matrix[c][d] <0){
            printf("Not possible");
            exit(0);
 }
          else{*/

          printf("%3d ",matrix[i][d]);
        }
      printf("\n");
    }