Language: C++

3 3 1
2 1 2 3
.@.
.@.
.@.#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
using namespace std;
using namespace __gnu_pbds;

#define TRACE

#ifdef TRACE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1>
void __f(const char* name, Arg1&& arg1){
	cerr << name << " : " << arg1 << std::endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args){
	const char* comma = strchr(names + 1, ',');cerr.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
}
#else
#define trace(...)
#endif

#define lsc(x)      scanf("%lld",&x)
#define sc(x)       scanf("%d",&x)
#define lpr(x)      printf("%lld ",(long long)x)
#define pr(x)       printf("%d ",x)
#define n_l         printf("\n")
#define VI          vector<int>
#define VII         vector<long long int>
#define m_p         make_pair
#define pb          push_back
#define fi           first
#define se           second
#define mset(x,y)   memset(x,y,sizeof(x))
#define sz(v)       (int)v.size()
#define all(v)      v.begin(), v.end()
#define fr(i, a, n) for(int i=a;i<=n;i++)
#define FIO ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
mt19937 rng32(chrono::steady_clock::now().time_since_epoch().count());
const int N=(int)1e6+5;
const int mod = 1000000007;
typedef long long ll;
// order_of_key (val): returns the no. of values strictly less than val
// find_by_order (k): returns the kth largest element iterator.(0-based)
// vector<int>::iterator itr=lower_bound(v.begin(),v.end(),x);
// s.substr(pos[0-indexed], len(default=till end))
typedef tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

ll fmod(ll x){if (x<mod) return x;return x%mod;}
ll mul(ll a, ll b, ll c){
	ll ret=0;while(b){if (b%2) ret=(ret+a)%c;a=(a*2)%c;b>>=1;}
    return ret;
}
int modpow(ll a, ll b){
    ll ret=1;while(b){if (b%2) ret=(ret*a)%mod;a=(a*a)%mod;b>>=1;}
    return (int)ret;
}
inline int inv(int x){ return modpow(x, mod-2);}
int isprime[N];
void calc_prime(){
	isprime[1]=1;for(ll i=2;i<N;i++) if (!isprime[i]) for(ll j=i*i;j<N;j+=i) isprime[j]=1;
}
int h, w, k;
vector<VI> area, dis, vis;
set<pair<int, int> >s;
int X[4] = {0, 0, 1, -1};
int Y[4] = {1, -1, 0, 0};
int main(){
    //FIO;
    cin>>h>>w>>k;
    VI tmp(w+1, 0);
    area.pb(tmp);
    VI tmp1(w+1, mod);
    int x1, y1, x2, y2;
    cin>>x1>>y1>>x2>>y2;
    fr(i, 1, h+1){
        dis.pb(tmp1);
        vis.pb(tmp);
    }
    fr(i,1,h){
        string s;cin>>s;
        int cnt = 1;
        for (auto c: s) {
            if (c == '.') tmp[cnt] = 1;
            else tmp[cnt]=0;
            cnt++;
        }
        area.pb(tmp);
    }
    dis[x1][y1] = 0;
    vis[x1][y1] = 1;
    s.insert({x1, y1});
    while(s.size()){
        auto pp = *s.begin();
        // trace(pp.fi, pp.se);
        s.erase(pp);
        fr(i, 0, 3){
            fr(j, 1, k){
                int resx = pp.fi + X[i]*j;
                int resy = pp.se + Y[i]*j;
                // trace(resx, resy);
                if (resx<1 or resx > h or resy<1 or resy>w) break;
                if (!area[resx][resy]) break;
                if (dis[resx][resy] <= dis[pp.fi][pp.se]+1) break;
                if(vis[resx][resy]) continue;
                // trace(resx, resy);
                vis[resx][resy]=1;
                dis[resx][resy] = dis[pp.fi][pp.se]+1;
                s.insert({resx, resy});
            }
        }
    }
    pr(dis[x2][y2] == mod ? -1: dis[x2][y2]);n_l;

    return 0;
}



Compiler output:
a.cc:3:2: error: stray '@' in program
    3 | .@.
      |  ^
a.cc:4:2: error: stray '@' in program
    4 | .@.
      |  ^
a.cc:5:2: error: stray '@' in program
    5 | .@.#include<bits/stdc++.h>
      |  ^
a.cc:5:4: error: stray '#' in program
    5 | .@.#include<bits/stdc++.h>
      |    ^
a.cc:1:1: error: expected unqualified-id before numeric constant
    1 | 3 3 1
      | ^
In file included from /usr/include/c++/14/ext/typelist.h:46,
                 from /usr/include/c++/14/ext/pb_ds/assoc_container.hpp:45,
                 from a.cc:6:
/usr/include/c++/14/ext/type_traits.h:164:35: error: 'constexpr const bool __gnu_cxx::__is_null_pointer' redeclared as different kind of entity
  164 |   __is_null_pointer(std::nullptr_t)
      |                                   ^
/usr/include/c++/14/ext/type_traits.h:159:5: note: previous declaration 'template<class _Type> constexpr bool __gnu_cxx::__is_null_pointer(_Type)'
  159 |     __is_null_pointer(_Type)
      |     ^~~~~~~~~~~~~~~~~
/usr/include/c++/14/ext/type_traits.h:164:26: error: 'nullptr_t' is not a member of 'std'
  164 |   __is_null_pointer(std::nullptr_t)
      |                          ^~~~~~~~~
In file included from /usr/include/c++/14/bits/stl_pair.h:60,
                 from /usr/include/c++/14/utility:69,
                 from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:46,
                 from /usr/include/c++/14/ext/pb_ds/tag_and_trait.hpp:46,
                 from /usr/include/c++/14/ext/pb_ds/assoc_container.hpp:46:
/usr/include/c++/14/type_traits:666:33: error: 'nullptr_t' is not a member of 'std'; did you mean 'nullptr_t'?
  666 |     struct is_null_pointer<std::nullptr_t>
      |                                 ^~~~~~~~~
In file included from /usr/include/c++/14/cstddef:50,
                 from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:45:
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:443:29: note: 'nullptr_t' declared here
  443 |   typedef decltype(nullptr) nullptr_t;
      |                             ^~~~~~~~~
/usr/include/c++/14/type_traits:666:42: error: template argument 1 is invalid
  666 |     struct is_null_pointer<std::nullptr_t>
      |                                          ^
/usr/include/c++/14/type_traits:670:48: error: template argument 1 is invalid
  670 |     struct is_null_pointer<const std::nullptr_t>
      |                                                ^
/usr/include/c++/14/type_traits:674:51: error: template argument 1 is invalid
  674 |     struct is_null_pointer<volatile std::nullptr_t>
      |                                                   ^
/usr/include/c++/14/type_traits:678:57: error: template argument 1 is invalid
  678 |     struct is_null_pointer<const volatile std::nullptr_t>
      |                                                         ^
/usr/include/c++/14/type_traits:1429:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1429 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1429:57: error: template argument 1 is invalid
 1429 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                                         ^
/usr/include/c++/14/type_traits:1429:57: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1438:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1438 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1438:46: error: template argument 1 is invalid
 1438 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/14/type_traits:1438:46: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1440:26: error: 'std::size_t' has not been declared
 1440 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:1441:21: error: '_Size' was not declared in this scope
 1441 |     struct rank<_Tp[_Size]>
      |                     ^~~~~
/usr/include/c++/14/type_traits:1441:27: error: template argument 1 is invalid
 1441 |     struct rank<_Tp[_Size]>
      |                           ^
/usr/include/c++/14/type_traits:1442:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1442 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1442:65: error: template argument 1 is invalid
 1442 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/14/type_traits:1442:65: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1446:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1446 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1446:65: error: template argument 1 is invalid
 1446 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/14/type_traits:1446:65: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:2086:26: error: 'std::size_t' has not been declared
 2086 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:2087:30: error: '_Size' was not declared in this scope
 2087 |     struct remove_extent<_Tp[_Size]>
      |                              ^~~~~
/usr/include/c++/14/type_traits:2087:36: error: template argument 1 is invalid
 2087 |     struct remove_extent<_Tp[_Size]>
      |                                    ^
/usr/include/c++/14/type_traits:2099:26: error: 'std::size_t' has not been declared
 2099 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:2100:35: error: '_Size' was not declared in this scope
 2100 |     struct remove_all_extents<_Tp[_Size]>
      |                                   ^~~~~
/usr/include/c++/14/type_traits:2100:41: error: template argument 1 is invalid
 2100 |     struct remove_all_extents<_Tp[_Size]>
      |                                         ^
/usr/include/c++/14/type_traits:2171:12: error: 'std::size_t' has not been declared
 2171 |   template<std::size_t _Len>
      |            ^~~
/usr/include/c++/14/type_traits:2176:30: error: '_Len' was not declared in this scope
 2176 |         unsigned char __data[_Len];
      |                              ^~~~
/usr/include/c++/14/type_traits:2194:12: error: 'std::size_t' has not been declared
 2194 |   template<std::size_t _Len, std::size_t _Align =
      |            ^~~
/usr/include/c++/14/type_traits:2194:30: error: 'std::size_t' has not been declared
 2194 |   template<std::size_t _Len, std::size_t _Align =
      |                              ^~~
/usr/include/c++/14/type_traits:2195:55: error: '_Len' was not declared in this scope
 2195 |            __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                       ^~~~
/usr/include/c++/14/type_traits:2195:59: error: template argument 1 is invalid
 2195 |            __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                           ^
/usr/include/c++/14/type_traits:2202:30: error: '_Len' was not declared in this scope
 2202 |         unsigned char __data[_Len];
      |                              ^~~~
/usr/include/c++/14/type_traits:2203:44: error: '_Align' was not declared in this scope
 2203 |         struct __attribute__((__aligned__((_Align)))) { } __align;
      |                                            ^~~~~~
In file included from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:47:
/usr/include/c++/14/tr1/type_traits:153:26: error: 'std::size_t' has not been declared
  153 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/tr1/type_traits:154:25: error: '_Size' was not declared in this scope
  154 |     struct is_array<_Tp[_Size]>
      |                         ^~~~~
/usr/include/c++/14/tr1/type_traits:154:31: error: template argument 1 is invalid
  154 |     struct is_array<_Tp[_Size]>
      |                               ^
/usr/include/c++/14/tr1/type_traits:354:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  354 |     : public integral_constant<std::size_t, __alignof__(_Tp)> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/tr1/type_traits:354:61: error: template argument 1 is invalid
  354 |     : public integral_constant<std::size_t, __alignof__(_Tp)> { };
      |                                                             ^
/usr/include/c++/14/tr1/type_traits:354:61: note: invalid template non-type parameter
/usr/include/c++/14/tr1/type_traits:359:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  359 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | t