Z-2

#include <iostream>
#include <string>
#include <fstream>
#include <queue>

using namespace std;

const int N = 1111;
const int INF = 1e9;
const int dx[] = {-1, -2, -2, -1, 1, 2, 2, 1}, dy[] = {-2, -1, 1, 2, 2, 1, -1, -2};
int a[N][N], n, m, d[N][N], cur, xs, ys, xf, yf;
queue<int> qx[3], qy[3];

void bfs() {
    qx[cur].push(xs);
    qy[cur].push(ys);
    d[xs][ys] = 0;
    while (!qx[0].empty() || !qx[1].empty() || !qx[2].empty()) {
        int x = qx[cur].front(), y = qy[cur].front();
        qx[cur].pop(); qy[cur].pop();
        for (int t = 0; t < 8; ++t) {
            int tx = x + dx[t], ty = y + dy[t];
            if (tx < 1 || tx > n || ty < 1 || ty > m || a[tx][ty] == -1) continue;
            int w = 1 + a[tx][ty];
            if (d[tx][ty] > d[x][y] + w) {
                d[tx][ty] = d[x][y] + w;
                qx[(cur + w) % 3].push(tx);
                qy[(cur + w) % 3].push(ty);
            }
        }
        if (qx[cur].empty()) cur = (cur + 1) % 3;
        if (qx[cur].empty()) cur = (cur + 1) % 3;
    }
}

int main(){
    ifstream fin("in.txt");
    ofstream fout("out.txt");
    fin >> n >> m;
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j) {
            fin >> a[i][j];
            d[i][j] = INF;
        }
    fin >> xs >> ys >> xf >> yf;
    bfs();
    if (d[n][m] < INF) fout << d[xf][yf];
    else fout << "No";
    return 0;
}