切り餅発見伝

rect.cc

#include <iostream>
#include <vector>
#include <string>
#include <fstream>

typedef std::vector<std::string> Table;
typedef unsigned long long int ullint;

ullint rectnum(const Table&);

void subnum(const Table&,unsigned,unsigned,ullint&);

int main(int argc,char **argv){
  std::ifstream ifs("in.txt");
  Table table;
  std::string in;
  unsigned n,m;
  ifs>>n>>m;
  // std::cin>>n>>m;
  for(int i=0;i<n;++i){
    ifs>>in;
    // std::cin>>in;
    table.push_back(in);
    // table.push_back(std::string(m,'#'));
  }

  std::cout<<rectnum(table)<<std::endl;
  return 0;
}

ullint rectnum(const Table& table){
  ullint num=0;
  unsigned maxy=table.size()-2;
  unsigned maxx=table[0].size()-2;
  for(unsigned y=0;y<maxy;++y){
    for(unsigned x=0;x<maxx;++x){
      if(table[y][x]=='#'&&table[y+1][x]=='#'&&table[y][x+1]=='#'
          &&table[y+2][x]=='#'&&table[y][x+2]=='#')
        subnum(table,x,y,num);
    }
  }
  return num;
}

void subnum(const Table& table,unsigned px,unsigned py,ullint& num){ 
  unsigned maxx,maxy;
  unsigned i,x,y;
  for(maxx=2;maxx<(table[0].size()-px)&&table[py][px+maxx]=='#';maxx++);
  for(maxy=2;maxy<(table.size()-py)&&table[py+maxy][px]=='#';maxy++);

  for(y=2;y<maxy;++y){
    for(x=0;x<maxx&&table[py+y][px+x]=='#';++x){
      if(x>=2){
        for(i=0;i<y&&table[py+i][px+x]=='#';++i);
        if(i==y)num++;
      }
    }
  }
}