UVa 447 - Population Explosion

Accepted date: 2015-04-10
Ranking (as of 2015-04-10): 91 out of 454
Language: C++

/*
  UVa 447 - Population Explosion

  To build using Visual Studio 2012:
    cl -EHsc -O2 UVa_447_Population_Explosion.cpp
*/

#include <algorithm>
#include <cstdio>
using namespace std;

const int nr_quarters = 20;

char quarters[2][nr_quarters][nr_quarters + 1];

void init_quarters(char q[nr_quarters][nr_quarters + 1])
{
  for (int i = 0; i < nr_quarters; i++)
    for (int j = 0; j < nr_quarters; j++)
      q[i][j] = ' ';
}

void print_quarters(char q[nr_quarters][nr_quarters + 1])
{
  puts("********************");
  for (int i = 0; i < nr_quarters; i++)
    puts(q[i]);
}

int main()
{
  const int nr_dirs = 8;
  int dirs[nr_dirs][2] =
    {{1, 0}, {1, 1}, {0, 1}, {-1, 1}, {-1, 0}, {-1, -1}, {0, -1}, {1, -1}};

  int nr_cases;
  scanf("%d", &nr_cases);
  while (nr_cases--) {
    int nr_years;
    scanf("%d", &nr_years);
    while (getchar() != '\n')
      ;
    char (*pq)[nr_quarters][nr_quarters + 1] = &quarters[0],
      (*cq)[nr_quarters][nr_quarters + 1] = &quarters[1];
    init_quarters(*pq);
    int c;
    while ((c = getchar()) != '\n' && c != EOF) {
      ungetc(c, stdin);
      int i, j;
      scanf("%d %d", &i, &j);
      (*pq)[i - 1][j - 1] = 'O';
      while (getchar() != '\n')
        ;
    }
    if (nr_years--)
      print_quarters(*pq);
    while (nr_years-- > 0) {
      init_quarters(*cq);
      for (int i = 0; i < nr_quarters; i++)
        for (int j = 0; j < nr_quarters; j++) {
          int n = 0;
          for (int k = 0; k < nr_dirs; k++) {
            int ci = i + dirs[k][0], cj = j + dirs[k][1];
            if (ci >= 0 && ci < nr_quarters && cj >= 0 && cj < nr_quarters &&
              (*pq)[ci][cj] == 'O')
              n++;
          }
          if ((*pq)[i][j] == 'O') {
            if (n == 2 || n == 3)
              (*cq)[i][j] = 'O';
          }
          else {
            if (n == 3)
              (*cq)[i][j] = 'O';
          }
        }
      print_quarters(*cq);
      swap(pq, cq);
    }
    puts("********************");
    if (nr_cases)
      putchar('\n');
  }
  return 0;
}