제출 #960605

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
960605		LmaoLmao	Mecho (IOI09_mecho)	C++14	0 / 100	3 ms	604 KiB

mecho

#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
 
using ll = long long;
using ii = pair<int, int>;
 
const int N = 1e6+5;
const int INF = 1e9;

ll d[1000][1000],m[1000][1000],n,s;
char a[1000][1000];
ll dx[4]={1,0,0,-1};
ll dy[4]={0,1,-1,0};
ii pos,h;

bool bfs(ll x) {
    queue<ii> q;
    q.push(pos);
    for(int i=0;i<n;i++) {
        for(int j=0;j<n;j++) {
            m[i][j]=0;
        }
    }
    while(!q.empty()) {
      	if(d[pos.fi][pos.se]-x*s<=0) return 0;
        ii u=q.front();
        q.pop();
        for(int i=0;i<4;i++) {
            ii v={u.fi+dx[i],u.se+dy[i]};
            if(v.fi<0 || v.fi>=n || v.se<0 || v.se>=n) continue;
            if(m[v.fi][v.se]==0 && a[v.fi][v.se]!='T' && 
            d[v.fi][v.se]-x*s>m[u.fi][u.se]+1 && a[v.fi][v.se]!='M') {
                m[v.fi][v.se]=m[u.fi][u.se]+1;
                q.push(v);
            }
        }
    }
    if(m[h.fi][h.se]>0) return 1; else return 0;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #ifndef ONLINE_JUDGE
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
    #endif
    queue<ii> q;
    cin >> n >> s;
    for(int i=0;i<n;i++) {
        for(int j=0;j<n;j++) {
            cin >> a[i][j];
            if(a[i][j]=='H') {
                q.push({i,j});
            }
            if(a[i][j]=='M') pos={i,j};
            if(a[i][j]=='D') h={i,j};
        }
    }
    while(!q.empty()) {
        ii u=q.front();
        q.pop();
        for(int i=0;i<4;i++) {
            ii v={u.fi+dx[i],u.se+dy[i]};
            if(v.fi<0 || v.fi>=n || v.se<0 || v.se>=n) continue;
            if(d[v.fi][v.se]==0 && a[v.fi][v.se]!='T' && a[v.fi][v.se]!='H') {
                d[v.fi][v.se]=d[u.fi][u.se]+s;
                q.push(v);
            }
        }
    }
    ll l=0,r=1000000,ans=1;
    while(l<=r) {
        int m=(l+r)/2;
        if(bfs(m)) {
            ans=m;
            l=m+1;
        }
        else {
            r=m-1;
        }
    }
    cout << ans;
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

mecho.cpp: In function 'int main()':
mecho.cpp:48:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |     freopen("in.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:49:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   49 |     freopen("out.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 100