제출 #762778

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
762778		bLIC	Mecho (IOI09_mecho)	C++17	18 / 100	233 ms	6396 KiB

mecho

/**
 *  Author: Anil Byar
**/

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>

// using namespace __gnu_pbds;
using namespace std;

// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define uniq(v) v.erase(unique(all(v)), v.end())
#define ft first
#define sd second
#define pb push_back
#define eb emplace_back

// Source: https://codeforces.com/blog/entry/68809
// { start
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end


typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;

#define dbg if(0)

const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;

void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}

template<class T>
istream& operator>>(istream&in, vector<T>&v){
    for (T& x:v) in>>x;
    return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
    for (T& x:v) out<<x<<' ';
    cout<<'\n';
    return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp
// Read the statement carefully

const int maxN = 1;
const int maxK = 8001;

int dx[] = {1, 0, 0, -1};
int dy[] = {0, 1, -1, 0};

void solve(){
    int n, s;cin>>n>>s;
    vector<string> grid(n);
    for (int i = 0;i<n;i++) cin>>grid[i];

    vvi beetime(n, vi(n, INF));
    queue<pii> q;
    for (int i = 0;i<n;i++) for (int j = 0;j<n;j++) if (grid[i][j]=='H') {
        q.emplace(i, j);
        beetime[i][j] = 0;
    }
    while(!q.empty()){
        auto [x, y] = q.front();q.pop();
        int tim = beetime[x][y] + 1;
        for (int i = 0;i<4;i++){
            int xx = x+dx[i];
            int yy = y+dy[i];
            if (xx<0 || xx>=n || yy<0 || yy>=n || tim>=beetime[xx][yy] || grid[xx][yy]=='T' || grid[xx][yy]=='D'){
                continue;
            }
            beetime[xx][yy] = tim;
            q.emplace(xx, yy);
        }
    }

    auto check = [&](int m){
        vvi mtim(n, vi(n, INF));
        queue<array<int, 3>> qq;
        int fx, fy;
        for (int i = 0;i<n;i++){
            for (int j = 0;j<n;j++){
                if (grid[i][j]=='M'){
                    qq.push({i, j, 0});
                    mtim[i][j] = m;
                } else if (grid[i][j]=='D') fx=i, fy = j;
            }
        }
        vector<vector<bool>> poss(n, vector<bool>(n, false));

        while(!qq.empty()){
            auto [x, y, step] = qq.front();qq.pop();
            poss[x][y] = true;
            step++;
            int tim = mtim[x][y];
            if (step==1) tim++;
            if (step==s) step = 0;
            for (int i = 0;i<4;i++){
                int xx = x+dx[i];
                int yy = y+dy[i];
                if (xx<0 || yy<0 || xx>=n || yy>=n || grid[xx][yy]=='T' || tim>=beetime[xx][yy] || tim>=mtim[xx][yy]){
                    continue;
                }
                mtim[xx][yy] = tim;
                qq.push({xx, yy, step});
            }
        }
        if (poss[fx][fy]) return true;

        mtim.assign(n, vi(n, INF));
        mtim[fx][fy] = 0;
        while(!q.empty()) q.pop();
        q.emplace(fx, fy);
    
        while(!q.empty()){
            auto [x, y] = q.front();q.pop();
            if (poss[x][y]) return true;

            int tim = mtim[x][y] + 1;
            for (int i = 0;i<4;i++){
                int xx = x+dx[i];
                int yy = y+dy[i];
                if (xx<0 || xx>=n || yy<0 || yy>=n || grid[xx][yy]=='T' || tim>= mtim[xx][yy] || tim>s){
                    continue;
                }
                mtim[xx][yy] = tim;
                q.emplace(xx, yy);
            }
        }
        
        return false;
    };

    int l = -1, r = INF;
    while(r-l>1){
        int mid = (l+r)/2;
        if (check(mid)) l = mid;
        else r = mid;
    } 
    cout<<l;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);


#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
    freopen("debug.dbg", "w", stderr);
    int tt = clock();
#endif

    int t=1, i = 1;
    // cin>>t;
    while(t--){
        // cout<<"Case #"<<i++<<": ";
        solve();
        cout<<'\n';
    }
#ifndef ONLINE_JUDGE
    cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
    tt = clock();
#endif
}

컴파일 시 표준 에러 (stderr) 메시지

mecho.cpp: In function 'int main()':
mecho.cpp:206:14: warning: unused variable 'i' [-Wunused-variable]
  206 |     int t=1, i = 1;
      |              ^

• Subtask 1: 18 / 100