제출 #1267179

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1267179		CodeLakVN	Mecho (IOI09_mecho)	C++20	100 / 100	169 ms	6216 KiB

mecho

#include <bits/stdc++.h>
using namespace std;

#define task "main"
#define F first
#define S second
#define ii pair<int, int>
#define il pair<int, long long>
#define li pair<long long, int>
#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FOD(i, b, a) for(int i = (b); i >= (a); --i)
#define valid(x, y) ((x) >= 1 && (x) <= n && (y) >= 1 && (y) <= n)

template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }

template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }

template <class T>
    void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
        for(auto item: container) out << item << separator;
        out << finish;
    }

const int MAX_N = (int)803;
const int INF = (int)1e9 + 1408;
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, 1, 0, -1};

int n, speed;
string forest[MAX_N];

int sX, sY, tX, tY;

int distBee[MAX_N][MAX_N], distBear[MAX_N][MAX_N];

void bfs(int dist[MAX_N][MAX_N], int val) {
    queue<ii> q;
    FOR(i, 1, n) FOR(j, 1, n) if (dist[i][j] == 0)
        q.push({i, j});

    while (!q.empty()) {
        int x = q.front().F, y = q.front().S;
        q.pop();

        if (val >= 0 && dist[x][y] / speed + val >= distBee[x][y])
            continue;

        FOR(i, 0, 3) {
            int newX = x + dx[i], newY = y + dy[i];
            if (!valid(newX, newY)) continue;
            if ((val >=  0 || forest[newX][newY] != 'D') && forest[newX][newY] != 'T' && dist[newX][newY] >= INF) {
                dist[newX][newY] = dist[x][y] + 1;
                q.push({newX, newY});
            }
        }
    }
}

void solve() {
    cin >> n >> speed;
    FOR(i, 1, n) {
        cin >> forest[i];
        forest[i] = "@" + forest[i];
    }

    FOR(i, 1, n) FOR(j, 1, n) {
        if (forest[i][j] == 'M') sX = i, sY = j;
        else if (forest[i][j] == 'D') tX = i, tY = j;
    }

    memset(distBee, 0x3f, sizeof(distBee));
    FOR(i, 1, n) FOR(j, 1, n) if (forest[i][j] == 'H')
        distBee[i][j] = 0;
    bfs(distBee, -1);

    int l = 0, r = n * n, res = -1;
    while (l <= r) {
        int mid = (l + r) >> 1;

        memset(distBear, 0x3f, sizeof(distBear));
        distBear[sX][sY] = 0;
        bfs(distBear, mid);

        if (distBear[tX][tY] < INF) l = (res = mid) + 1;
        else r = mid - 1;
    }

    cout << res;
}

int32_t main() {
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    bool multitest = 0;
    int numTest = 1;
    if (multitest) cin >> numTest;

    while (numTest--) {
        solve();
    }

    return 0;
}

/* Lak lu theo dieu nhac!!!! */

컴파일 시 표준 에러 (stderr) 메시지

mecho.cpp: In function 'int32_t main()':
mecho.cpp:101:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:102:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  102 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100