ОИ-2 bfs лабиринт mkG()

#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <stack>
#include <set>
#include <map>
#define pii pair <int,int>
#define vec vector
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
void cv(vector <int> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvl(vector <ll> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}


void cvv(vector <vector <int> > &v){
    for (auto x: v) cv(x);
    cout<<"\n";
}


vector < vector < vector<pii> > > G;
//vector[0] - слева - пара (x,y)
//vec[1] - справа
//vec[2] - сверху
//vec[3] - снизу
vector <vector<int>> dsk;
vector <vector <int> > dist;

const int inf = 2e9;

int n,m;
bool gd(pii x){
    return x.first >= 0 && x.first < n && x.second >= 0 && x.second < m && dsk[x.first][x.second] != 1;
}

void shG(){
    for (int i=0;i<n;++i){
        for (int j=0;j<m;++j){
            cout<<"("<<i<<","<<j<<") \n";
            for (int k = 0;k<4;++k){
                cout<<G[i][j][k].first<<' '<<G[i][j][k].second<<"\n";
            }
        }

    }cout<<"\n";
}


//
void shdsk(){
    for (int i=0;i<n;++i){
        for (int j=0;j<m;++j){
            cout<<dsk[i][j]<<' ';
        }cout<<"\n";
    }cout<<"\n";
}

void mkG(){
    //NB!!! учитывай, что если мы приходили в вершину v или u другим путем, то там НЕ НАДО изменять G(v)/G(u)!!!
    //добавб: не только if G(v)[direction] == {-1, -1} -> G(v)[direction] = u
    //НО И if G(u)[dir] == {-1, -1} -> G(u)[direction] = v;
    //vector[0] - слева - пара (x,y)
    //vec[1] - справа
    //vec[2] - сверху
    //vec[3] - снизу
    queue <pii> go;
    go.push({0,0});
    pii v, u;
    while (!go.empty()){
        v = go.front();
        if (G[v.first][v.second][0] == pii {-1, -1}){
            //слева
            while (gd({u.first, u.second-1})){
                u.second--;
            }
            if (u != v){
                G[v.first][v.second][0] = u;
                if (G[u.first][u.second][1] == pii {-1,-1}) G[u.first][u.second][1] = v;
                go.push(u);
            }
        }
        if (G[v.first][v.second][1] == pii {-1, -1}){
            //справа
            u = v;
            while (gd({u.first, u.second+1})){
                u.second++;
            }
            if (u != v){
                G[v.first][v.second][1] = u;
                if (G[u.first][u.second][0] == pii {-1,-1}) G[u.first][u.second][0] = v;
                go.push(u);
            }
        }
        if (G[v.first][v.second][2] == pii {-1, -1}){
            //сверху
            u = v;
            while (gd({u.first-1, u.second})){
                u.first--;
            }
            if (u != v){
                G[v.first][v.second][2] = u;
                if (G[u.first][u.second][3] == pii {-1,-1}) G[u.first][u.second][3] = v;
                go.push(u);
            }
        }
        if (G[v.first][v.second][3] == pii {-1, -1}){
            //снизу
            u = v;
            while (gd({u.first+1, u.second})){
                u.first++;
            }
            if (u != v){
                G[v.first][v.second][3] = u;
                if (G[u.first][u.second][2] == pii {-1,-1}) G[u.first][u.second][2] = v;
                go.push(u);
            }

        }
        go.pop();
    }
}

int main()
{
    ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

	//cin>>n>>m;
	n = 18;
	m = 14;
	dist.resize(n, vector <int> (m , inf));
	dsk.resize(n, vector <int>(m,0));
	for (int i=0;i<n;++i){
        for (int j=0;j<m;++j) continue ;//cin>>dsk[i][j];
	}
	//строим G
	//for (int i = 1; i <= 7;++i) dsk[i][0] = 1;
	for (int j = 5; j<=9;++j) dsk[0][j] = 1;
	for (int i=0;i<=7;++i) dsk[i][7] = 1;
	for (int i = 1;i<=3;++i) dsk[i][10]  =1;
	for (int j = 1;j<=6;++j) dsk[9][j] = 1;
	for (int i=5;i<=9;++i) dsk[i][10] = 1;
	for (int j=8;j<=10;++j) dsk[9][j] = 1;
	for (int i=4;i<=8;++i) dsk[i][12] = 1;
	for (int j=3;j<=4;++j) dsk[13][j] = 1;
	vector <pii> pnt = { {14, 2}, {14, 5}, {15, 4}, {16, 6}, {12, 12}, {13, 11}, {14, 10}, {15, 9}, {15, 12}, {16, 11} };
	for (int i=0;i<pnt.size();++i){
        dsk[pnt[i].first][pnt[i].second] = 1;
	}
	shdsk();
	G.resize(n, vector <vector <pii> > (m, vector <pii> (4, {-1, -1})));
	mkG();
	shG();

}
/*
4 5
0 0 0 0 1
0 1 1 0 2
0 2 1 2 0
0 0 1 0 0
*/