JOI2018-yo-5.cpp

#include <bits/stdc++.h>
 
using namespace std;
 
//#define int long long
#define FOR(i, j, k) for(int i = j; i < k; ++i)
#define rep(i, j) FOR(i, 0, j)
#define INF 1e9
#define LINF 1e18
#define fi first
#define se second
 
typedef unsigned long long ull;
typedef pair<int, int> P;
typedef pair<int, P> Pi;
typedef pair<P, P> PP;
 
const int MOD = 1e9 + 7;
const int dy[] = { 0, 0, 1, -1 };
const int dx[] = { 1, -1, 0, 0 };
 
template <class T> void chmin(T& a, const T& b) { a = min(a, b); }
template <class T> void chmax(T& a, const T& b) { a = max(a, b); }
 
int H, W, A[30][30];
P dist[31][31];
 
int bfs() {
    queue<P> que;
    que.push(P(0, 0));
    
    while(!que.empty()) {
        P p = que.front(); que.pop();
        int x = p.second, y = p.first;
        rep(i, 4) {
            int nx = x + dx[i], ny = y + dy[i];
            if(0 <= nx && nx < W && 0 <= ny && ny < H) {
                if(dist[ny][nx].fi > dist[y][x].fi + dist[y][x].se * A[ny][nx] * 2 + A[ny][nx]) {
                    dist[ny][nx].fi = dist[y][x].fi + dist[y][x].se * A[ny][nx] * 2 + A[ny][nx];
                    dist[ny][nx].se = dist[y][x].se + 1;
                    que.push(P(ny, nx));
                }
            }
        }
    }
    return dist[H - 1][W - 1].fi;
}
 
signed main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
 
    cin >> H >> W;
    rep(i, H) rep(j, W) {
        dist[i][j].fi = INF;
        cin >> A[i][j];
    }
    dist[0][0].fi = 0;
    cout << bfs() << endl;
    return 0;
}