PrintFrame.cc

#include <iostream>
#include <cmath>
#include <sstream>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <numeric>

int main()
{
  int w,h;

  while (std::cin >> w >> h) {
    if (w==0) {
      continue;
    }
    for (int x=0;x<w;x++) {
      for (int y=0;y<h;y++) {
        if (y==0||y==h-1||x==0||x==w-1) {
          std::cout << "#";
        }
        else {
          std::cout << ".";
        }
      }
      std::cout << std::endl;
    }
    std::cout << std::endl;
  }

  return 0;
}