Thread: sum of neighbors in matrix - can't get past second matrix

The homework assignment is to get the sum of each entry in the grid plus its neighbors, then put that into a new grid based on some rules that can be seen in

Code:

int sumOfNeighbors

. That part works fine. I can get the first two grids to come up right, but we need it to work for any number of grids for

Code:

int gen  = 'number of grids here'

. I feel like I've tried it a million ways and can't get past the second generation unless I code it for a specific number of grids, which isn't the way we are supposed to do it. I tried making a tempGrid to move grid2 into grid1, but grid1 still always comes back as the first grid?

Example output would be:

Gen 1
15 7 4 5 39 27 15 12 63	adds up to ->	66 97 77 93 187 152 71 161 141
Gen 2	<-rules applied to sums makes gen 2
63 94 74 90 1 1 68 1 138	adds up to->	248 323 170 317 530 309 160 299 141
Gen 3	<-rules applied to sums makes gen 3
1 1 0 1 0 1 0 1 1

Any nudge in the right direction would be much appreciated! Thanks in advance

Code:

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

#define ROWS 3
#define COLS 3

int seed = 29;
int high = 40;
int gen = 4;
int grid1[ROWS][COLS];     
int grid2[ROWS][COLS];       
int tempGrid[ROWS][COLS];          
int size = sizeof grid1 / sizeof *grid1;

int sumOfNeighbors(int grid[][COLS], int row, int col, int count){
  int i, j, sum = 0;

  for(i = row - 1; i <= row + 1; i ++){
    for(j = col - 1; j <= col + 1; j++){
      if( i >= 0 && i <= size - 1 && j >= 0 && j <= size - 1){
        sum += grid[i][j];
      }
    }
  }

  //printf("\n\nSUM: %d\n\n", sum);

  //If the sum is % 10 -> self = 0
  if(sum % 10 == 0){
    grid[i][j] = 0;
  }
  //if the sum is under 50 -> add 3 to self
  else if(sum < 50){
    grid[i][j] = sum + 3;
  }
  // if sume is over 50 and less than 150 -> substract 3 from self (can't be less than 0)
  else if(sum > 50 && sum < 150){
    if(sum <= 0){
      grid[i][j] = 0;
    }
    else{
      grid[i][j] = sum - 3;
    }
  }
  // if the sum is over 150 -> self = 1
  else{
    grid[i][j] = 1;
  }
  
  sum = grid[i][j];

  return sum;
}


void printArray(int grid[][COLS], int row, int col){
  for(int i = 0; i < row; i++){
    printf("\n");
    for(int j = 0; j < col; j++){
      printf("%3d ", grid[i][j]);
    }
  }
  printf("\n\n");
}

void fillGrid(int grid[][COLS], int row, int col){

  srand(seed);

  for(int i = 0; i < row; i++){
    for(int j = 0; j < col; j++){
      grid[i][j] = rand() % high;
    }
  }
}


void createNewGrid(int grid[][COLS], int row, int col){
  int count = 1;
  int k, i, j, num = 0;

  for(k = 0; k < gen; k++){
    for(i = 0; i < ROWS; i++){
      for(j = 0; j < COLS; j++){   
        num = sumOfNeighbors(grid, i, j, count);
        grid2[i][j] = num;
        tempGrid[i][j] = grid2[i][j];
        //printf("TEMP GRID BELOW\n");
        //printArray(tempGrid, ROWS, COLS);
    }
  }
    
  if(count % 2 == 1){
    printf("----GEN %d----\n", count);
    printArray(grid, ROWS, COLS);
  }
  else{
    printf("----GEN %d----\n", count);
    printArray(grid2, ROWS, COLS);
  }
  count ++;
  }
  for(i = 0; i < ROWS; i++){
    for(j = 0; j < COLS; j++){ 
      grid1[i][j] = tempGrid[i][j];
      //printf("GRID 1 BELOW\n");
      //printArray(grid1, ROWS, COLS);
    }
  }

}


int main(){
  /*
  int count = 1;
  int num = 0;
  */

  fillGrid(grid1, ROWS, COLS);

  createNewGrid(grid1, ROWS, COLS);

}