Sat Apr 20 17:13:28 2024

Algorithmic Cryptanalysis (View it on amazon.com)

A CRC Press Book by Antoine Joux

Program 3.1: Basic matrix multiplication

Algorithmic cryptanalysis codes by Antoine Joux are licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License.

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

#define DIM 32
#define REPEAT 100000

void input_mat(int mat[DIM][DIM])
{
  int l,c;

  for (l=0;l<DIM;l++) {
    for (c=0;c<DIM;c++) {

      scanf("%d",&mat[l][c]);
    }
  }
}

void print_mat(int mat[DIM][DIM])
{

  int l,c;
  for (l=0;l<DIM;l++) {

    for (c=0;c<DIM;c++) {
      printf("%d ",mat[l][c]);
    }

    printf("\n");
  }
}

void Mul(int res[DIM][DIM], int mat1[DIM][DIM], int mat2[DIM][DIM])
{

  int l,c,k;
  for (l=0;l<DIM;l++) {

    for (c=0;c<DIM;c++) { res[l][c]=0;

      for (k=0;k<DIM;k++) {
        res[l][c]+=mat1[l][k]*mat2[k][c];
      }

      res[l][c]%=2;
    }
  }
}

main()
{
  int mat1[DIM][DIM]; int mat2[DIM][DIM];

  int mat3[DIM][DIM]; int count;
  printf("Input Mat1\n");  input_mat(mat1);

  printf("Input Mat2\n");  input_mat(mat2);
  for (count=0;count<REPEAT;count++) Mul(mat3,mat1,mat2);

  printf("Product :\n");  print_mat(mat3);
}

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