magic21

/*
   THIS PROGRAM SIMULATES A MAGIC TRICK WITH 21 CARDS
   by: randerson112358
*/

# include <stdio.h>

void shuffle(int arr[][3], int arr2[][3]);
void updateArray (int arr[][3], int arr2[][3]);
void swap(int arr[][3], int x, int y);
void printMatrix(int arr[][3]);

int main(void)
{

    int inRow=0;
    int turn=0;
    int TRUE = 1, FALSE=0;
    
    //Creating 7 X 3 MATRIX
    int arr[7][3] = {
                     {1,2,3},
                     {4,5,6},
                     {7,8,9},
                     {10,11,12},
                     {13,14,15},
                     {16,17,18},
                     {19,20,21}};
    
    int arr2[7][3] = {
                     {1,2,3},
                     {4,5,6},
                     {7,8,9},
                     {10,11,12},
                     {13,14,15},
                     {16,17,18},
                     {19,20,21}};
                     
    printf("Welcome to the Magic game\n");  
    do{
         
         printf("Please remember a number in this matrix\n");
         printMatrix(arr2);
         printf("Please Enter the row number your number is in: ");
         scanf("%d",&inRow);
         if(inRow == 2)
         {
              shuffle(arr,arr2);
         }
         else if(inRow == 1)
         {
              swap(arr2,inRow-1,1);
              updateArray(arr,arr2); // arr = arr2
              shuffle(arr,arr2);
         }
         else if(inRow == 3)
         {
              swap(arr2,inRow-1,1);
              updateArray(arr,arr2); 
              shuffle(arr,arr2);
         }
         

         //TO ALLOW A USER TO CHOOSE THE MIDDLE CARD ON FIRST TURN
         if(inRow == 2 && turn !=0)
         TRUE = FALSE;
         
         turn++;
         system("cls");//clear screen windows command (optional)
    
    }while(TRUE );
    
    //THE LAST SHUFFLE AFTER THE USER INPUTS 2ND ROW, THIS SHUFFLE WILL PLACE THE NUMBER IN SPOT 11
    //the last shuffle after they tell the card is in the 2nd row
    printMatrix(arr2);
    printf("Please Enter the row number your number is in: ");
         scanf("%d",&inRow);
    if(inRow == 2)// if the card is already in the second row, no need to change rows for correct shuffle
         {
              shuffle(arr,arr2);
         }
         else if(inRow == 1)// swap row 1 with row 2, in matrix its row 0 with row 1
         {
              swap(arr2,inRow-1,1);
              updateArray(arr,arr2); // arr = arr2
              shuffle(arr,arr2);
         }
         else if(inRow == 3)// swap row 3 with row 2, in matrix its row 2 with row 1
         {
              swap(arr2,inRow-1,1);
              updateArray(arr,arr2); 
              shuffle(arr,arr2);
         }
     printf("Your number is %d, I just read your mind FOOL! \n", arr[3][1]);// the answer is always the 11th card which is located in arr[3][1]
     // note if I were to print the matrix right now, the users number would be in the 11th spot arr[3][1]
     //printMatrix(arr2);   //<---- uncomment if u dont believe me
    system("pause");
}

/////////////////////////////////////////// FUNCTIONS///////////////////////////////////////////////////////////////////
// Does the shuffling according to 1row then second row then third row
void shuffle(int arr[][3], int arr2[][3])
{
      int i,j,k=0,count =1;
      
      for(j=0; j<3; j++)
     {
       for(i=0; i<7; i++){ 
                  arr2[k][((i%3)+j)%3] = arr[i][j];
                  if(count%3 == 0)
                  k++;
                  
                  count++;
        }
      }
     updateArray(arr,arr2);
}
//This updates matrix arr, arr = arr2 where arr2 is the new matrix
void updateArray (int arr[][3], int arr2[][3])
{
     int i,j;
     for(i=0; i<7; i++)
        for(j=0; j<3; j++)
         arr[i][j] = arr2[i][j];
     
}
//swap() swaps the columns of the matrix so that the shuffle works properly 
void swap(int arr[][3], int x, int y)
{
     int i=0;
     for(i=0; i<7; i++)
     {
              int temp = arr[i][x];
              arr[i][x] = arr[i][y];
              arr[i][y] = temp;
     }
}
//prints the matrix
void printMatrix(int arr[][3])
{
     int i,j;
     printf("Row1\tRow2\tRow3\t\n");
     for(i=0;i<7;i++)
     {
      for(j=0;j<3;j++)
      {
        printf("%d \t", arr[i][j]);
      }
      printf("\n");
     }//*/
}