#include <string>
#include <vector>
#include <list>
#include <cmath>
#include <algorithm>
#include <map>
#include <set>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <sys/time.h>
using namespace std;

#define VIT(i, v) for (i = 0; i < v.size(); i++) 
#define IT(it, ds) for (it = ds.begin(); it != ds.end(); it++)
#define FUP(i, n) for (i = 0; i < n; i++)

typedef vector <int> IVec;
typedef vector <double> DVec;
typedef vector <string> SVec;

void usage(string s)
{
  fprintf(stderr, "usage: mm r1 c1/r2 c2 blocksize seed(-1=time(0)) print(y|n)\n");
  if (s != "") fprintf(stderr, "%s\n", s.c_str());
  exit(1);
}
  
class MM {
  public:
    vector <double> M1;
    vector <double> M2;
    vector <double> P;
    int r1, c1, c2;
    int Print;
    int Blocksize;
    void MultiplyBlock(int row1, int col1, int col2);
    void Multiply();
    void PrintAll();
};

void MM::MultiplyBlock(int row1, int col1, int col2)
{
  int pr, pc, tmp;

  for (pr = row1; pr < ((row1 + Blocksize > r1) ? r1 : row1 + Blocksize); pr++) {
    for (pc = col2; pc < ((col2 + Blocksize > c2) ? c2 : col2 + Blocksize); pc++) {
      for (tmp = col1; tmp < ((col1 + Blocksize > c1) ? c1 : col1 + Blocksize); tmp++) {
        P[pr*c2+pc] += (M1[pr*c1+tmp] * M2[pc*c1+tmp]);
      }
    }
  }
}

void MM::Multiply()
{
  int row1, col1, col2;

  for (row1 = 0; row1 < r1; row1 += Blocksize) {
    for (col2 = 0; col2 < c2; col2 += Blocksize) {
      for (col1 = 0; col1 < c1; col1 += Blocksize) {
        MultiplyBlock(row1, col1, col2);
      }
    }
  }
}

void MM::PrintAll()
{
  int i, j;

  printf("M1: %d x %d\n\n", r1, c1);
  for (i = 0; i < r1; i++) {
    for (j = 0; j < c1; j++) printf(" %6.4lf", M1[i*c1+j]);
    printf("\n");
  }
    printf("\n");

  printf("M2: %d x %d\n\n", c1, c2);
  for (i = 0; i < c1; i++) {
    for (j = 0; j < c2; j++) printf(" %6.4lf", M2[j*c1+i]);
    printf("\n");
  }
    printf("\n");

  printf("P: %d x %d\n\n", r1, c2);
  for (i = 0; i < r1; i++) {
    for (j = 0; j < c2; j++) printf(" %6.4lf", P[i*c2+j]);
    printf("\n");
  }
}

int main(int argc, char **argv)
{
  MM *M;
  int r1, c1, c2, i, j, bs;
  string s;
  long seed;
  double t0, t1;
  struct timeval tv;
  
  if (argc != 7) usage("");
  M = new MM;

  if (sscanf(argv[1], "%d", &r1) == 0 || r1 <= 0) usage("Bad r1");
  if (sscanf(argv[2], "%d", &c1) == 0 || c1 <= 0) usage("Bad c1/r2");
  if (sscanf(argv[3], "%d", &c2) == 0 || c2 <= 0) usage("Bad c2");
  if (sscanf(argv[4], "%d", &bs) == 0 || bs <= 0) usage("Bad bs");

  M->r1 = r1;
  M->c1 = c1;
  M->c2 = c2;
  M->Blocksize = bs;

  seed = 0;
  sscanf(argv[5], "%ld", &seed);
  if (seed == -1) seed = time(0);
  srand48(seed);

  s = argv[6];
  if (s == "y") {
    M->Print = 1;
  } else if (s == "n") {
    M->Print = 0;
  } else usage("Bad print");

  M->M1.resize(r1*c1);
  M->M2.resize(c1*c2);
  M->P.resize(r1*c2, 0);

  for(i = 0; i < r1*c1; i++) M->M1[i] = drand48()*2.0;
  for(i = 0; i < c1; i++) {
    for(j = 0; j < c2; j++) M->M2[j*c1+i] = drand48()*2.0;
  }
  
  gettimeofday(&tv, NULL);
  t0 = tv.tv_usec;
  t0 /= 1000000.0;
  t0 += tv.tv_sec;

  M->Multiply();

  gettimeofday(&tv, NULL);
  t1 = tv.tv_usec;
  t1 /= 1000000.0;
  t1 += tv.tv_sec;

  if (M->Print) M->PrintAll();

  printf("Time: %.4lf\n", t1-t0);
  exit(0);
}