#include<iostream>
#include<cstdlib>
using namespace std;
const int size = 20;

int oldmap[size][size];
int newmap[size][size];

void createmap();
void printmap();
void update();
void copy();

int main(){
  createmap();
  printmap();
  update();
  copy();
  cout << endl;
  printmap();
}

void update(){
  int sum;
  for(int y = 0; y < size; y++){
     for(int x = 0; x < size; x++){
         // set newmap value based on oldmap values
         // newmap[x][y] = something about the sum of neighbors oldmap
         sum = 0;
         if(x>0 && y>0)
	         sum = oldmap[x-1][y-1];
         if(y>0)
     		 sum += oldmap[x][y-1];
         if(x<size-1 && y > 0)
		sum += oldmap[x+1][y-1];
	 if(x > 0)
	         sum += oldmap[x-1][y];
         if(x < size -1)
 		 sum += oldmap[x+1][y];
         if(x > 0 && y < size -1)
	         sum += oldmap[x-1][y+1];
	if(y < size -1)
 	         sum += oldmap[x][y+1];
        if(x < size -1 && y < size -1)
		 sum += oldmap[x+1][y+1];
        newmap[x][y] = 0;
	if(sum == 3)
                 newmap[x][y] = 1;
        if(sum == 2 && oldmap[x][y] == 1)
   		newmap[x][y] = 1;
     }
  }
}

void copy(){
  for(int y = 0; y < size; y++){
     for(int x = 0; x < size; x++){
        oldmap[x][y] = newmap[x][y];
     }
  }
}

void printmap(){
  for(int y = 0; y < size; y++){
     for(int x = 0; x < size; x++){
        cout << oldmap[x][y];
     }
     cout << endl;
  }
}

void createmap(){
  for(int y = 0; y < size; y++){
     for(int x = 0; x < size; x++){
        oldmap[x][y] = rand()%2;
     }
  }
}