Finding an array that is at minimum distance from a group of arrays.

MinDistArray.c

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

float distance(int *, int *, int);
void printArr(int *, int, int, char *);
void printMat(int **, int, int, char *);

int main(int argc, char const *argv[])
{
   int i, j, k, rnd;
   int nSize, nPerms;
   int *univ, **perm, **pos;

   int tempSum;
   int tempMin, tempPos;
   int *sum, *ansp, *ans;

   float tempDist, finalDist;

   srand(time(0));

   printf("\nEnter size of array: "); scanf("%d", &nSize);
   printf("\nEnter number of permutations: "); scanf("%d", &nPerms);

   univ = (int *)malloc(nSize * sizeof(int));

   perm = (int **)malloc(nPerms * sizeof(int *));
   for (i = 0; i < nPerms; i++)
      perm[i] = (int *)malloc(nSize * sizeof(int));

   pos = (int **)malloc(nPerms * sizeof(int *));
   for (i = 0; i < nPerms; i++)
      pos[i] = (int *)malloc(nSize * sizeof(int));

   sum = (int *)malloc(nSize * sizeof(int));
   ansp = (int *)malloc(nSize * sizeof(int));
   ans  = (int *)malloc(nSize * sizeof(int));

   for (i = 0; i < nSize; i++)
      univ[i] = i+1;

   for (i = 0; i < nPerms; i++)
   {
      for (j = 0; j < nSize; j++)
      {
         // Random number between 0 and j
         rnd = (j == 0) ? 0 : (rand() % (j+1));

         if (rnd != j)
            perm[i][j] = perm[i][rnd];

         perm[i][rnd] = univ[j];
      }
   }

   // printMat(perm, nPerms, nSize, "Permutation");

   for (i = 0; i < nPerms; i++)
   {
      for (j = 1; j <= nSize; j++)
      {
         for(k = 0; k < nSize; k++)
         {
            if (j == perm[i][k])
               break;
         }
         pos[i][j-1] = k+1;
      }
   }

   // printMat(pos, nPerms, nSize, "Position");

   for (j = 0; j < nSize; j++)
   {
      tempSum = 0;
      for (i = 0; i < nPerms; i++)
      {
         tempSum += pos[i][j];
      }
      sum[j] = tempSum;
   }

   // printArr(sum, nSize, 0, "Sum       ");

   for(i = 0; i < nSize; i++)
   {
      tempMin = sum[i]; tempPos = i;
      for (j = 0; j < nSize; j++)
      {
         if (sum[j] < tempMin)
         {
            tempMin = sum[j];
            tempPos = j;
         }
      }
      ansp[i] = tempPos; sum[tempPos] = RAND_MAX;
   }

   // printArr(ansp, nSize, 1, "AnswerP   ");

   for(i = 0; i < nSize; i++)
      ans[ansp[i]] = i+1;

   printArr(ans, nSize, 0, "Answer    ");

   printf("\n\n");

   finalDist = 0;
   for(i = 0; i < nPerms; i++)
   {
      tempDist = distance(ans, pos[i], nSize);
      finalDist += tempDist;
   }

   printf("\n\nThe distance of answer from all permutations is: %f \n", finalDist/nPerms);

   return 0;
}

float distance(int *arr1, int *arr2, int size)
{
   int i = 0;
   float dist = 0;

   for(i = 0; i < size; i++)
      dist += abs(arr1[i] - arr2[i]);

   return (dist / (0.5 * size * (size)));
}

void printArr(int *arr, int size, int adj, char *str)
{
   int i;

   printf("\n%s \t: ", str);
   for (i = 0; i < size; i++)
   {
      printf("%3d ", arr[i] + adj);
   }
}

void printMat(int **mat, int row, int col, char *str)
{
   int i, j;

   printf("\n");
   for (i = 0; i < row; i++)
   {
      printf("%s %d\t: ", str, i+1);

      for (j = 0; j < col; j++)
         printf("%3d ", mat[i][j]);

      printf("\n");
   }
}