Submission #1120843

#	Time	Username	Problem	Language	Result	Execution time	Memory
1120843		vjudge1	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	839 ms	224276 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()

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;
    deque<pii>dq;
    dq.pb({1,1});
    int x,y,gox,goy;
    while(!dq.empty())
    {
        x = dq.front().first;
        y = dq.front().second;
        dq.pop_front();
        for(size_t i = 0; i < 4; ++i)
        {
            gox = x + dx[i];
            goy = y + dy[i];
            if(inbound(gox,goy) && a[gox][goy] != '.' &&  dp[gox][goy] == 0)
            {
                if(a[gox][goy] == a[x][y])
                {
                    dp[gox][goy] = dp[x][y];
                    dq.push_front({gox,goy});
                }
                else
                {
                    dp[gox][goy] = dp[x][y] + 1;
                    dq.pb({gox,goy});
                }
            }
        }
    }
}

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: 30 / 30
• Subtask 2: 70 / 70