#include <stdio.h>
#include <sys/time.h>
#include <stdlib.h>

const int maxsize=700;
const int maxnum=10;

void matrixFromFile(int** mat, 
		    int rows, int cols, char* filename)
{
    FILE *infile;
    int i, j;
   
    if ((infile=fopen(filename, "r")) == NULL) {
        printf("Could not open file\n");
        exit(0);
    }
    for(i=0; i<rows; i++) {
       for(j=0;j < cols; j++) { 
           fscanf(infile,"%d", &mat[i][j]);
       }
    }
    fclose(infile);
}

int checkMatrices(int** m, int** n, 
		    int rows, int cols)
{
    int i, j;
    
    for(i=0; i<rows; i++)
       for(j=0;j < cols; j++)
           if (m[i][j] != n[i][j]) {
		printf("Different at %d, %d\n", i,j);
	        return 0;
	   }
    return 1;
}

void matMult(int** m, int** n, int** prod, 
		int rows1, int cols1, int rows2, int cols2)
{
    int i, j, k;

/*  INSERT YOUR CODE HERE  */

}


void printMatrix(int** m)
{
    int i, j;

    for(i=0; i<maxsize; i++)  {
        for(j=0;j < maxsize; j++) {
            printf("%5d", m[i][j]);
        }
        printf("\n");
    }
}

int main()
{
    int rows1 = 500, cols1 = 500;
    int rows2 = 500, cols2 = 500;
    int** m;
    int** n;
    int** prod;
    int** prod2;

    char *filename1 = "matrix500.txt";
    char *filename2 = "matrix500B.txt";
    char *filename3 = "prod500.txt";

    struct timeval tv;
    struct timezone tz;
    long starttimeSec, starttimeMicro;
    long endtimeSec, endtimeMicro;
    long totalSec, totalMicro;   

    m = (int**)malloc(sizeof(int*)*rows1);
    int i;
    for (i = 0; i < rows1; i++) {
	    m[i] = (int*)malloc(sizeof(int)*cols1);
    }
    n = (int**)malloc(sizeof(int*)*rows2);
    for (i = 0; i < rows2; i++) {
	    n[i] = (int*)malloc(sizeof(int)*cols2);
    }
    prod = (int**)malloc(sizeof(int*)*rows1);
    for (i = 0; i < rows1; i++) {
	    prod[i] = (int*)malloc(sizeof(int)*cols2);
    }
    prod2 = (int**)malloc(sizeof(int*)*rows1);
    for (i = 0; i < rows1; i++) {
	    prod2[i] = (int*)malloc(sizeof(int)*cols2);
    }


    printf("Reading first matrix...\n");
    matrixFromFile(m, rows1, cols1, filename1);
    printf("Reading second matrix...\n");
    matrixFromFile(n, rows2, cols2, filename2);
    printf("Starting matrix multiplication...\n");
    gettimeofday(&tv, &tz);
    starttimeSec = tv.tv_sec;
    starttimeMicro = tv.tv_usec;
    matMult(m,n,prod, rows1, cols1, rows2, cols2);
    gettimeofday(&tv, &tz);
    endtimeSec = tv.tv_sec;
    endtimeMicro = tv.tv_usec;

    printf("Ending matrix multiplication.\n");
    if (endtimeSec > starttimeSec)
    {
       totalSec = endtimeSec-starttimeSec;
       totalMicro = endtimeMicro + (1000000 - starttimeMicro);
    } else {
        totalSec = 0;
	totalMicro = endtimeMicro - starttimeMicro;
     }	
      
     printf("Time = %d sec, %d microsec\n", totalSec, totalMicro);
   
    printf("Reading solution product...\n");
    matrixFromFile(prod2, rows1, cols2, filename3);
    printf("Check matrix multiplication...\n");
    if (checkMatrices(prod,prod2, rows1, cols2))
	 printf("Congratulations, you agree with my answer\n");
    else
	 printf("Sorry, we disagree\n");

    for (i = 0; i < rows1; i++) {
	free(m[i]);
	}
	free(m);
    for (i = 0; i < rows2; i++) {
	free(n[i]);
	}
	free(n);
    for (i = 0; i < rows1; i++) {
	free(prod[i]);
	}
	free(prod);
    for (i = 0; i < rows1; i++) {
	free(prod2[i]);
	}
	free(prod2);

    return 0;
}