Submission #1120817

#	Time	Username	Problem	Language	Result	Execution time	Memory
1120817		vjudge1	Tracks in the Snow (BOI13_tracks)	C++17	31.77 / 100	1667 ms	141928 KiB

tracks

/*
#ifndef ONLINE_JUDGE
#include "AkbarKING.h" // aska geldi akbarking.h
#else
#define debug(...)
#define debugArr(...)
#define debugG(...)
#endif
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/hash_policy.hpp>

#define int long long
#define $AzH_TxdmN$ ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
#pragma GCC target("sse,sse2,sse3,ssse3,popcnt,abm,mmx,tune=native")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("no-stack-protector")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("fast-math")

#define ep emplace_back
#define pb push_back
#define pii pair<int,int>
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()

#define heap pii, vector<pii>, less<pii>
using namespace std;
using namespace __gnu_pbds;

template <typename T>
using __indexed_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <typename T>
using __indexed_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

const int sz = 4e3 +9;
const int LOG = 63;
const int MOD = 1e9+7;
const int INF = 1e18;
int dx[] = {-1,0,1,0};
int dy[] = {0,1,0,-1};
int dp[sz][sz];
bool used[sz][sz];
char a[sz][sz];

int n,m;

bool inbound(const int &a, const int &b)
{
    return 1 <= a && 1 <= b && a <= n && b <= m;
}

void djk()
{
    dp[1][1] = 1;
    priority_queue<heap> q;
    q.push({ 1, 1 });
    while(!q.empty())
    {
        int i, j;
        tie(i, j) = q.top();
        q.pop();
        for(int t = 0; t <= 3; t ++)
        {
            int u = i + dx[t], v = j + dy[t];
            if(inbound(u, v) && a[u][v] != '.' &&  dp[u][v] == 0)
            {
                if(a[u][v] == a[i][j])
                {
                    dp[u][v] = dp[i][j];
                    q.push({ u, v });
                }
                else
                {
                    dp[u][v] = dp[i][j] + 1;
                    q.push({ u, v });
                }
            }
        }
    }
}

void solve()
{
    cin>>n>>m;
    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            cin>>a[i][j];
        }
    }
    djk();
    int res = 0;
    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            res = max(res,dp[i][j]);
        }
    }
    cout<<res<<'\n';
}

signed main()
{
    $AzH_TxdmN$
    int t = 1;
    //cin>>t;
    while (t--)
    {
        solve();
    }
}

• Subtask 1: 3.3333333333333335 / 30
• Subtask 2: 28.4375 / 70