#include <iostream> #include <iomanip> #include <cstdio> #include <cstring> #include <vector> #include <array> #include <deque> #include <list> #include <forward_list> #include <set> #include <map> #include <unordered_set> #include <unordered_map> #include <queue> #include <stack> #include <string> #include <sstream> #include <cstring> #include <algorithm> #include <functional> #include <numeric> #include <utility> #include <bitset> #include <tuple> #include <optional> #include <variant> #include <cmath> #include <cstdlib> #include <cstdint> #include <climits> #include <limits> #include <random> #include <chrono> #include <fstream> #include <iterator> #include <regex> #include <type_traits> #include <cctype> #include <cstddef> #define name "DISPERSAL" #define ii pair<int,int> #define se second #define fi first using namespace std; using ll = long long; const int inf = 1e9; int mx[]={0,1,0,-1}, my[]={1,0,-1,0}; const int N = 305; int r,c,n; ii Q[N]; bool ok(int x,int y){ return x>0 and x<=r and y>0 and y<=c; } namespace sub1{ bool a[5][5]; int check[1<<17]; int backtrack(int mask,int cur,int type=0){ // cout<<type<<'\n'; // cout<<bitset<12>(mask)<<" "<<cur<<'\n'; // for(int i=1;i<=r;++i){ // for(int j=1;j<=c;++j){ // cout<<a[i][j]; // } // cout<<'\n'; // } // cout<<'\n'; if(mask==((1<<c*r)-1)) return cur; if(check[mask]!=inf) return check[mask]; bool tmp[5][5]; for(int i=1;i<=r;++i){ for(int j=1;j<=c;++j){ tmp[i][j] = a[i][j]; } } for(int t=0;t<4;++t){ for(int i=1;i<=r;++i){ for(int j=1;j<=c;++j){ int x = i+mx[t], y = j+my[t]; if(!ok(x,y))continue; a[x][y] |= tmp[i][j]; } } int premask=mask; for(int i=1;i<=r;++i){ for(int j=1;j<=c;++j){ if(a[i][j]==1)premask |= (1<<((i-1)*c+j-1)); } } if(mask!=premask) check[mask] = min(check[mask],backtrack(premask,cur+1,t)); for(int i=1;i<=r;++i){ for(int j=1;j<=c;++j){ a[i][j] = tmp[i][j]; } } } return check[mask]; } void solve(){ for(int mask=0; mask<(1<<17); ++mask) check[mask]=inf; int mask = 0; for(int i=1;i<=n;++i){ a[Q[i].fi][Q[i].se] = 1; mask |= (1<<((Q[i].fi-1)*c+Q[i].se-1)); } cout<<backtrack(mask,0); } } signed main(){ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); if(fopen(name".inp","r")){ freopen(name".inp","r",stdin); freopen(name".out","w",stdout); } cin>>r>>c>>n; for(int i=1;i<=n;++i){ cin>>Q[i].fi>>Q[i].se; } sub1::solve(); }

cultivation.cpp: In function 'int main()':
cultivation.cpp:139:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  139 |         freopen(name".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
cultivation.cpp:140:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  140 |         freopen(name".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~