hakan - bwt

hakan.c

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

#define TRUE 1
#define FALSE 0

typedef char bool;


int cmp_rows(const void * a, const void * b) {
    printf("compare: | %s | %s |", a,b);
    return strcmp(a,b);
}


int main () {

    FILE *fp = fopen("hakan.in", "r");

    //get filesize
    fseek(fp, 0L, SEEK_END);
    long file_size = ftell(fp);
    fseek(fp, 0L, SEEK_SET);

    file_size = file_size - 1;


    // allocate table
    char **table = (char **)malloc(file_size * sizeof(char *));
	for(long i = 0; i < file_size; i++)  {
		table[i] = (char *)malloc(file_size * sizeof(char));
    }

    // read file - first row in table
    char c = 0;
    long pos = 0;
    while ((c = fgetc(fp)) != EOF ){
        table[0][pos] = c;
        pos++;
    } 

    // do mutations
    for (long i=1; i<file_size; i++) {
        for (long j=0; j<file_size; j++) {
            long copy_pos = j - 1;
            if (copy_pos < 0) {
               copy_pos = file_size -1;
            }
            table[i][j] = table[i-1][copy_pos];
        }
    }

    //print table
    for (long i=0; i<file_size; i++) {
        for (long j=0; j<file_size; j++) {
            printf("%c",  table[i][j]);
        }
        printf("\n");
    }

    // sort
    qsort(table, file_size, file_size*sizeof(char *), cmp_rows);
   
    //print table
    for (long i=0; i<file_size; i++) {
        for (long j=0; j<file_size; j++) {
            printf("%c",  table[i][j]);
        }
        printf("\n");
    }

    fclose(fp);   
    return 0;
}