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

extern void pmatrix(int n,double A[n][n]);

extern void mkA(int n,double A[n][n],int s);
 
extern void AtA(int n,double B[n][n],double A[n][n]);
  
extern void Ax(int n,double y[n],
        double A[n][n],double x[n]);

extern double dotprod(int n,double x[n],double y[n]);

extern double fnorm(int n,double A[n][n]);